Which methods for "thinking out computalion" Gie, mental arithmetic) are correct
a)7+8 Think: 7 plus 7 is 14, plus 1 more is 15
b) 38 - 17
Think: 38 minus 10 is 28, minus 7 more is 21
c) 999 x 3 Think: 1000 threes is 3000 minus 1 three is 2997
d) 150 ÷ 3 Think: what equals 150 x 3, that's 450

The probability of rolling a sum of 5 when rolling a 6-sided die twice is 1/9.

According to the Law of Large Numbers, a fundamental tenet of probability theory, the average of the results of an experiment approaches the predicted value of the random variable being measured as the number of trials in the experiment rises. In other words, the Law of Big Numbers states that the observed results will be closer to the predicted outcomes the more times an experiment is conducted.

The total number of outcomes when a die is rolled two times is 36.

The sum of 5 is obtained for the following outcomes:

(1,4), (2,3), (3,2), and (4,1)

Thus,

P(sum of 5) = 4/36 = 1/9

Hence, the probability of rolling a sum of 5 when rolling a 6-sided die twice is 1/9.

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In interval notation, the solution of the inequality is (25, ∞).

To solve the inequality x(x-7) < x^2 - 5x - 50, we can rearrange the terms and factor the quadratic expression:
x^2 - 7x < x^2 - 5x - 50
-2x < -50
x > 25

In interval notation, the solution is (25, ∞).

So, the answer is (25, ∞).

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The equation 3x² - 12x - 15 = 0 when solved by factoring has the solutions x = 5 and x = -1

The equation 3x² - 12x - 15 = 0, is a representation of the equation in the question.

The aforementioned problem is a quadratic equation, and factoring is one way to solve this kind of issue.

Divide 3 from the equation.

As a result, we have the following

x² - 4x - 5 = 0.

Expanding the equation, we get

x² + x - 5x - 5 = 0.

Factoring the equation, we get

x(x + 1) - 5(x + 1) = 0

The result is

(x - 5)(x + 1) = 0.

We can solve for x by getting

x = 5 and x = -1.

Thus, the equation's answers are 5 and -1.

And it means that there are actually two solutions to the equation.

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The rate of consumption of fuel of Matt's car is 37 miles per gallon (mpg).

Matt's car can travel a total distance of 555 miles.
The fuel required to travel the total distance is 15 gallons by Matt's car.
Hence the rate of consumption of fuel of Matt's car can be measured in mpg (miles per gallons) as = Total distance travelled / Total gallons required to travel that distance
(that is, total distance travelled divided by the total amount of gallons to travel the same)
Thus the mpg of Matt's car is = 555 miles / 15 gallons
= 37 miles per gallon
(that is 37 mpg)

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Answer: 11.6

Step-by-step explanation: plug in x for 4. 3.2(4)-1.2 = 11.6

Answer:

16

Step-by-step explanation:

g(x)=-5x+1

g(-3)

x=-3

-5(-3) +1

15+1

16

Answer:

See below.

Step-by-step explanation:

For this problem, we are asked to find the value of g(-3).

We are given a Linear Function.

A Linear Function is a Polynomial Function that is commonly graphed. This function most of the time will simply be represented as a straight line when graphed.

For this problem;

[tex]g(x)=-5x+1 \ Find \ g(-3).[/tex]

We simply need to substitute -3 in for x.

[tex]g(-3)=-5(-3)+1[/tex]

Simplify:

[tex]g(-3)=16.[/tex]

Our final answer is g(-3) = 16.

The recursive formula for an, the nth term of the sequence is a(n) = a(n - 1) + 2 where a(1) = 2

From the question, we have the following parameters that can be used in our computation:

2, 6, 10, 14, ....

The above definitions imply that we simply add 4 to the previous term to get the current term

Using the above as a guide,

So, we have the following representation

a(n) = a(n - 1) + 2

Hence, the sequence is a(n) = a(n - 1) + 2 where a(1) = 2

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The simple  interest values are all wrong

Simple Interest (S.I) is a method of charging or yielding a specific percentage on the principal amount borrowed/deposited in a particular period. It is calculated using the formula

SI = (Principal*Rate*Time)/100,

a) SI = (450*25.2*3)/100,

SI = %70.2

2) SI = (Principal*Rate*Time)/100,

SI = (250*3.75*5)/100,

$46.875

(3) SI = (Principal*Rate*Time)/100,

SI = (1800*2.1*2)/100,

SI = $75.6

4) SI = (Principal*Rate*Time)/100,

SI = (1500*2.9*2)/100,

SI = $87

5) SI = (Principal*Rate*Time)/100,

SI = (50*1.9*10)/100,

SI =$9.5

6) SI = (Principal*Rate*Time)/100,

SI = (8*0.7*300)/100,

SI = $16.8

7) SI = (Principal*Rate*Time)/100,

SI = (125*2.03*4)/100,

SI = $10.15

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Answer:

Let x be the score Natasha needs to earn on her next test to reach an average of 90%.

To find x, we can use the formula for the average:

average = (sum of scores) / (number of scores)

We know that Natasha has taken 5 tests so far, with scores of 94%, 89%, 88%, 92%, and 85%. We can plug these values into the formula and solve for x:

90% = (94% + 89% + 88% + 92% + 85% + x) / 6

Multiplying both sides by 6, we get:

540% = 448% + x

Subtracting 448% from both sides, we get:

92% = x

Therefore, Natasha needs to earn a score of at least 92% on her next test to reach an average of 90%.

The numbers for which the rational expression is undefined are x=0 and x=-4.

To find the numbers for which the rational expression (7x^(4)+8)/(5x^(2)+20x) is undefined, we need to find the values of x that make the denominator equal to zero. This is because division by zero is undefined.

So, we need to solve the equation 5x^(2)+20x=0 for x.

We can factor out a common factor of 5x from the equation:

5x(x+4)=0

Now, we can use the zero product property to set each factor equal to zero and solve for x:

5x=0 or x+4=0

x=0 or x=-4

So, the numbers for which the rational expression is undefined are x=0 and x=-4.

In summary, the rational expression (7x^(4)+8)/(5x^(2)+20x) is undefined for x=0 and x=-4.

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Answer:

D is the answer trust me

The probability that a randomly selected person had French toast for breakfast is 20%.

Probability describes the result of a random event based on the expected successes or outcomes.

Probability is computed as the quotient of the expected outcomes, events, or successes out of many possible outcomes, events, or successes.

Probability values lie between zero and one based on the degree of certainty or otherwise and can be depicted as percentages, decimals, or fractions.

The total number of survey participants = 20

The number of participants found to be having French toast for breakfast = 4

The probability of selecting a person having French toast for breakfast = 20%,or 0.2, or 1/5 (4/20 x 100)

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Step-by-step explanation:

Option A is the right answer.

The debt consolidation loan will cost Sheng an additional $1,997.69 in interest charges compared to his credit cards.

From question, we are to calculate how much more in interest the debt consolidation loan will cost Sheng

To calculate the interest charges for Sheng's credit cards, we need to use the following formula:

Interest Charges = Balance x APR x Number of Days in Billing Cycle / 365

Using this formula, we can calculate the interest charges for each of Sheng's credit cards:

For Credit Card A:

Interest Charges = $2,500 x 0.19 x 30 / 365 = $4.94

For Credit Card B:

Interest Charges = $3,000 x 0.22 x 30 / 365 = $6.01

So, the total interest charges for Sheng's credit cards are:

Total Interest Charges = $4.94 + $6.01 = $10.95

Now, let's calculate the total cost of the debt consolidation loan:

Total Cost = Total Monthly Payments x Number of Payments - Loan Amount

Total Monthly Payments = $179.37

Number of Payments = 6 x 12 = 72

Loan Amount = ?

To find the loan amount, we need to solve for it using the interest rate and the total interest charges:

Loan Amount = Total Interest Charges / (APR x Number of Payments / 12)

Loan Amount = $3,414.39 / (0.107 x 72 / 12) = $25,000

So, the total cost of the debt consolidation loan is:

Total Cost = $179.37 x 72 - $25,000 = $2,008.64

Therefore, the additional interest charges for the debt consolidation loan compared to Sheng's credit cards are:

Additional Interest Charges = Total Cost - Total Interest Charges

Additional Interest Charges = $2,008.64 - $10.95 = $1,997.69

Hence, the debt consolidation loan will cost him an additional $1,997.69 in interest charges

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Answer:

C

Step-by-step explanation:

Answer: c.

Step-by-step explanation:

Using the scale factors obtained the values are -

The value of k is 8, since g(−2) = 8.

The value of k is 8, since g(−2) = 8.

The value of k is 8, since g(−2) = 1.

The value of k is 4, since g(−2) = 2.

What is scale factor?

The scale factor of a shape refers to the amount by which it is increased or shrunk. It is applied when a 2D shape, such as a circle, triangle, square, or rectangle, needs to be made larger.

For each part, we can use the given table to determine how the transformation affects the function values -

g(x) = f(2x)

This transformation is a horizontal compression by a factor of 2.

To see this, notice that when we evaluate g at x = -1, we get the same value as f evaluated at x = -2.

Similarly, when we evaluate g at x = 0, we get the same value as f evaluated at x = 0.

And so on. In other words, the function values of g(x) are the same as the function values of f(x) at every other point (starting with x = -2).

So, g(x) is a compressed version of f(x) horizontally by a factor of 2.

Therefore, the value of k is 8, since g(−2) = 8 = f(2×(-2)).

g(x) = 2f(x)

This transformation is a vertical stretch by a factor of 2.

To see this, notice that every value of g(x) is twice the corresponding value of f(x).

So, g(x) is a stretched version of f(x) vertically by a factor of 2.

Therefore, the value of k is 8, since g(−2) = 2f(−2) = 2×4 = 8.

g(x) = f(x/2)

This transformation is a horizontal stretch by a factor of 2.

To see this, notice that when we evaluate g at x = -2, we get the same value as f evaluated at x = -4.

Similarly, when we evaluate g at x = -1, we get the same value as f evaluated at x = -2.

And so on. In other words, the function values of g(x) are the same as the function values of f(x) at every other point (starting with x = -4).

So, g(x) is a stretched version of f(x) horizontally by a factor of 2.

Therefore, the value of k is 8, since g(−2) = f(−1) = 1.

g(x) = (1/2)f(x)

This transformation is a vertical compression by a factor of 2.

To see this, notice that every value of g(x) is half the corresponding value of f(x).

So, g(x) is a compressed version of f(x) vertically by a factor of 2.

Therefore, the value of k is 4, since g(−2) = (1/2)f(−2) = (1/2)×4 = 2.

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Answer: 18

Step-by-step explanation

​

Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 27x, the least common multiple of 27,x.

x × 6=27 × 4

Multiply 27 and 4 to get 108.

x × 6=108

Divide both sides by 6.

x= 108/6

​

Divide 108 by 6 to get 18.

x=18

Answer:

Let's assume that the amount of saving is x.

According to the problem, the ratio of expenditure to saving is 4:1, so the amount of expenditure can be expressed as 4x.

The total income of the family is Rs. 500000, and it can be expressed as the sum of expenditure and saving:

Expenditure + Saving = 500000

Substituting the values of expenditure and saving, we get:

4x + x = 500000

Simplifying this equation, we get:

5x = 500000

Dividing both sides by 5, we get:

x = 100000

Therefore, the amount of saving is Rs. 100000, and the amount of expenditure is 4 times this value, which is Rs. 400000.

The domain of f⁻¹(x) is [0, ∞) and the range of f⁻¹(x) is [-3, ∞).

The function f(x)=(x+3)² is not one-to-one, as it is a quadratic function and has a parabolic shape. However, we can restrict the domain of the function so that it is one-to-one and increasing. One way to do this is to restrict the domain to be greater than or equal to the x-coordinate of the vertex of the parabola. The vertex of the parabola is at (-3, 0), so we can restrict the domain to be x ≥ -3. In interval notation, this is [-3, ∞).

The inverse function of f(x) can be found by switching the x and y values and solving for y. This gives us:

x = (y+3)²

√x = y+3

y = √x - 3

So the inverse function is f⁻¹(x) = √x - 3. The domain of the inverse function is the range of the original function, and the range of the inverse function is the domain of the original function. Therefore, the domain of f⁻¹(x) is [0, ∞) and the range of f⁻¹(x) is [-3, ∞).

In summary:

f(x)'s domain: [-3, ∞)

f⁻¹(x)'s domain: [0, ∞)

f(x)'s range: [0, ∞)

f⁻¹(x)'s range: [-3, ∞)

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Answer: what is ur questions?

Step-by-step explanation:

The average rate of change of f(x)=x^2+3x+1 from x=−5 to x=−3 is −5.

The average rate of change of a function f(x) over an interval [a,b] is given by the formula:
average rate of change = (f(b) - f(a)) / (b - a)

In this case, we are given the function f(x)=x^2+3x+1 and the interval [−5,−3], so we can plug in the values into the formula:
average rate of change = (f(−3) - f(−5)) / (−3 - (−5))

First, we need to find the values of f(−3) and f(−5):
f(−3) = (−3)^2 + 3(−3) + 1 = 9 − 9 + 1 = 1
f(−5) = (−5)^2 + 3(−5) + 1 = 25 − 15 + 1 = 11

Now, we can plug these values back into the formula:
average rate of change = (1 - 11) / (−3 - (−5)) = (−10) / 2 = −5

Therefore, the average rate of change of f(x)=x^2+3x+1 from x=−5 to x=−3 is −5.

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The answer is (1) x = 22.5; (2) x = 16.7; (3) x = 13.5; (4) x = 16.8; (5) x = 24.5; (6) x = 16.15; (7.a) height of the image on film is 11.2mm; (7.b) distance between camera and her friend is 1,875mm.

(1) We can see that in the given figure all three corresponding angles are congruent and all three corresponding sides are in equal proportion so, these are similar triangles.

As per properties of similar triangle:

Three pairs of corresponding sides are proportional i.e. Two pairs of corresponding sides are proportional and the corresponding angles between them are equal.

                        Therefore, [tex]\frac{32}{24} =\frac{30}{x}[/tex],

then by cross multiplying them, we get,

                                        32x = 720

                                            x = 720/32

                                           x = 22.5

(2) As, this is already given that these are similar triangle and by applying the properties of similar triangle we get,

                                           [tex]\frac{39}{26} =\frac{25}{x}[/tex]

                                         39x = 650

                                             x = [tex]16\frac{2}{3}[/tex]

                                            x = 16.7

(3) As these are similar triangle again we can say that,

                                        [tex]\frac{2x+1}{x+4} =\frac{40}{25}[/tex]

                                 40(x + 4) = 25(2x + 1)

                                40x + 160 = 50x + 25

                                          40x = 50x - 135

                                          -10x = -135

                 (by cancelling (-) sign from both sides we get,

                                              x = 135/10

                                             x = 13.5

(4) By applying similar triangle's property, we can get

                                           [tex]\frac{20}{30} =\frac{28-x}{x}[/tex]

                                         20x = 840 - 30x

                                         50x = 840

                                             x = 840/50

                                             x = 16.8

(5) As ΔJKL [tex]\sim[/tex] ΔNPR,

                                           [tex]\frac{KM}{PT} =\frac{KL}{PR}[/tex]

                                          [tex]\frac{18}{15.75} =\frac{28}{x}[/tex]

                                            18x = 441

                                                x = 441/18

                                               x = 24.5

(6) As ΔSTU [tex]\sim[/tex] ΔXYZ,

                                         [tex]\frac{UA}{ZB} =\frac{UT}{ZY}[/tex]

                                        [tex]\frac{6}{11.4} =\frac{8.5}{x}[/tex]

                                          6x = 96.6

                                            x = 96.6/6

                                            x = 16.15

(7.a) First we have to change 3 m and 140 cm into mm(millimeters).

So, 1m = 1000 mm

     3m = 3000mm.

And 1cm = 10 mm

   140cm = 1400 mm.

Then to find the height of the image on the film, we have to solve:

                                          [tex]\frac{24}{3000} =\frac{x}{1400}[/tex]

             by cross multiplication we get,

                                      3000x = 33,600

                                               x = 33,600/3000

                                              x = 11.2 mm

the height of the image on the film is 11.2millimeters.

(7.b) For this also, we have to find x by solving the equation:

                                            [tex]\frac{24}{3000} =\frac{15}{x}[/tex]

                                            24x = 45,000

                                                x = 45,000/24

                                              x = 1,875 mm

The distance between camera and her friend is 1,875 millimeters.

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Full question is given below in the image.

The probability of observing 2 heads is 1/4, the probability of observing 1 head is 2/4, and the probability of observing 0 heads is 1/4.

The question is asking what the probability of getting two heads (x=2) and one head (x=1) when tossing a coin.

The probability of getting two heads is P(x=2) = 1/4 and the probability of getting one head is P(x=1) = 2/4.

It is important to remember that the sum of all the probabilities in an experiment must equal 1.

In this case, P(x=2) + P(x=1) = 1/4 + 2/4 = 3/4. This means that the probability of observing 0 heads, represented as P(x=0), must be equal to 1/4 in order for the sum of all the probabilities to equal 1.

In conclusion, the variable x is used to represent the number of heads observed in a coin toss experiment, and the probabilities of observing different numbers of heads are given as fractions.

The probability of observing 2 heads is 1/4, the probability of observing 1 head is 2/4, and the probability of observing 0 heads is 1/4.

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Answer:

  q = 250,000·(0.6^t)

Step-by-step explanation:

You want an equation that models the graph of an exponential function that has an initial value of 250,000 and a value of 150,000 after 1 week.

An exponential function has the form ...

  q = a·b^t

where 'a' is the initial value, and 'b' is the decay factor over a period of one time unit of t.

The graph with this problem shows the initial value (for t=0) to be a=250,000. The decay factor will be ...

  b = 150,000/250,000 = 3/5 = 0.6

Then the exponential function can be written as ...

  q = 250000·(0.6^t) . . . . . . where t is in weeks

Dr. Bills Payable A/C 5,400 and Cr. Bank A/C 5,400

In the books of Brown:

Dr. Bank A/C 6,000

Cr. Bills Receivable A/C 6,000


On 3.2.2011:

Dr. Bills Receivable A/C 5,400

Cr. Bank A/C 5,400


On the due date:

Dr. Bills Receivable A/C 5,400

Cr. Black A/C 5,400


In the books of Black:

Dr. Bills Payable A/C 5,400

Cr. Bank A/C 5,400

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(a) The function combination (f + g)(x) is equal to x² - 3x + 12 and its domain are all real numbers.

(b) The function combination (f - g)(x) is equal to x² - 5x - 12 and its domain are all real numbers.

(c) The function combination (fg)(x) is equal to x³ + 8x² - 48x and its domain are all real numbers.

(d) The function combination (gf)(x) is equal to x³ + 8x² - 48x and its domain are all real numbers.

(a) To find the expression or value of the function combination (f + g)(x), we need to add f(x) and g(x).

(f + g)(x) = f(x) + g(x) = x² - 4x + x + 12 = x² - 3x + 12

Domain of (f + g)(x) : All real numbers

(b) To find the expression or value of the function combination (f - g)(x), we need to subtract g(x) from f(x).

(f - g)(x) = f(x) - g(x) = x² - 4x - (x + 12) = x² - 5x - 12

Domain of (f-g)(x) : All real numbers


(c) To find the expression or value of the function combination (fg)(x), we need to multiply the two functions.

(fg)(x) = f(x) * g(x) = (x² - 4x) (x + 12) = x³ + 8x² - 48x

Domain of (fg)(x) : All real numbers


(d) The function combination (gf)(x) is the same as (fg)(x).

(gf)(x) = g(x) * f(x) = (x + 12) (x² - 4x) = x³ + 8x² - 48x

Domain of (gf)(x) : All real numbers


In all cases, the domain is all real numbers because there are no restrictions on the values of x that can be used in the functions.

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The function is decreasing in the interval (3, ∞).

f(x) = -x² + 6x - 4

Differentiate the equation with respect to 'x'.

f'(x) = -2x + 6

Put f'(x) = 0

-2x + 6 = 0

x = 6/2

x = 3 (critical point)

Now, write the function as:

f(x) = -x² + 6x - 4

-(x² - 6x + 4) (negative form)

Thus, the function is decreasing in the interval (3, ∞)

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If the length of the flag is 12 ft more than its width, then the width of the flag is 30ft and length of the flag is 42ft.

Let "w" represent the width of the flag.

We know that the length of the flag is 12 feet more than its width, which means:

⇒ Length = w + 12

We also know that the perimeter of the flag is 144 feet,

The Perimeter of flag can be expressed as:

⇒ Perimeter = 2(Length + Width),

Substituting the expression for Length from above,

We get,

⇒ 144 = 2(w+12 + w)

Simplifying the equation:

We get,

⇒ 144 = 2(2w + 12)

⇒ 72 = 2w + 12

⇒ 60 = 2w

⇒ w = 30

So, width of flag is 30 feet. and Length = w + 12,

⇒ Length = 30 + 12

⇒ Length = 42

Therefore, the dimensions of the flag are 42feet by 30feet.

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The angle between \( \mathbf{u}=\langle-4,-1\rangle \) and \( \mathbf{v}=\langle-5,-2\rangle \) is approximately 12.5 degrees. To the nearest tenth of a degree, we can round this to 12.5 degrees.

To find the angle between two vectors \( \mathbf{u} \) and \( \mathbf{v} \), we can use the formula:
\[ \cos \theta = \frac{\mathbf{u} \cdot \mathbf{v}}{\| \mathbf{u} \| \| \mathbf{v} \|} \]
where \( \theta \) is the angle between the vectors, \( \mathbf{u} \cdot \mathbf{v} \) is the dot product of the vectors, and \( \| \mathbf{u} \| \) and \( \| \mathbf{v} \| \) are the magnitudes of the vectors.

First, we need to find the dot product of \( \mathbf{u} \) and \( \mathbf{v} \):
\[ \mathbf{u} \cdot \mathbf{v} = (-4)(-5) + (-1)(-2) = 20 + 2 = 22 \]

Next, we need to find the magnitudes of \( \mathbf{u} \) and \( \mathbf{v} \):
\[ \| \mathbf{u} \| = \sqrt{(-4)^2 + (-1)^2} = \sqrt{16 + 1} = \sqrt{17} \]
\[ \| \mathbf{v} \| = \sqrt{(-5)^2 + (-2)^2} = \sqrt{25 + 4} = \sqrt{29} \]

Now we can plug these values into the formula and solve for \( \theta \):
\[ \cos \theta = \frac{22}{\sqrt{17} \sqrt{29}} \]
\[ \theta = \cos^{-1} \left( \frac{22}{\sqrt{17} \sqrt{29}} \right) \]

Using a calculator, we find that \( \theta \approx 12.5 \) degrees.

Therefore, the angle between \( \mathbf{u}=\langle-4,-1\rangle \) and \( \mathbf{v}=\langle-5,-2\rangle \) is approximately 12.5 degrees. To the nearest tenth of a degree, we can round this to 12.5 degrees.

Learn more about Angle

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#SPJ11

Answer: To find the area of the white part of the billboard, we first need to find the area of the entire billboard and then subtract the area of the non-white part.

The area of a triangle can be found using the formula:

Area = (1/2) x base x height

In this case, the white part of the billboard is a right-angled triangle with a height of 4 ft and a base of 2.5 ft (half of the total base of 4.5 ft).

The area of the entire billboard is:

Area = (1/2) x base x height

Area = (1/2) x 4.5 ft x 4 ft

Area = 9 ft²

The area of the non-white part of the billboard is:

Area = (1/2) x base x height

Area = (1/2) x 2.5 ft x 4 ft

Area = 5 ft²

Therefore, the area of the white part of the billboard is:

Area of white part = Total area - Area of non-white part

Area of white part = 9 ft² - 5 ft²

Area of white part = 4 ft²

So the area of the white part of the billboard is 4 square feet.

Step-by-step explanation: