Solve the system of equations by graphing.
2x^2 + 8y^2 = 50
x^2 + y^2 = 13

Answers

Answer 1

The solutions for the given system are (3,2), (3,-2), (-3,2) and (-3,-2).

What is a Quadratic Function?

The quadratic function can represent a quadratic equation in the Standard form: ax²+bx+c=0 where: a, b and c are your respective coefficients. In the quadratic function the coefficient "a" must be different than zero (a≠0) and the degree of the function must be equal to 2.

The solution of these equations represents the points at which the parabolas intersect.

2x²+8y²=50 (1)

x²  + y²= 13 (2)

Multiplying the equation 2 by -2, you have:

2x²+8y²=50 (1)

-2x² -2 y²= -26(2)

Sum both equations, you have: 6y²= 24. Now, you can find y.

6y²= 24

y²=4

y=±2

If y=2, from equation 2, you have

x²  + y²= 13

x²  + 2²= 13

x²  + 4= 13

x² =13-4

x² =9

x=±3

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Related Questions

math help please right now!!!!

Answers

Answer:

The second answer is correct.

Step-by-step explanation:

Aria makes 12 dollars for each hour of work. Write an equation to represent her total pay, p, after working h hours.

Answers

Answer:

12×h=p

Step-by-step explanation:

if she works for 12 dollars per hour you multiply the 12 dollars buy the hours she worked to get the p

Seema had 150 marbles.rani had 20 marbles more than seema.alok had 50 marbles lass than rani how many marbles did rani have

Answers

Answer:

120

Step-by-step explanation:

seema 150 marbles

rani 20 more marbles

alok 50 less marble

150+20=170_rani

170-50=120_alok

Find the midpoint of the line segment
with endpoints (-4, 16) and (6, -10).

Answers

Answer:

B. (1,3)

Step-by-step explanation:

What is a midpoint?

Midpoint a point equidistant from the ends of a line or the extremities of a figure.

To find the midpoint of the line segment with endpoint, use the midpoint formula.

Midpoint formula:

[tex]\Rightarrow: \sf{\dfrac{x_2+x_1}{2}, \dfrac{y_2+y_1}{2} }}}[/tex]

y2=(-10)

y1=16

x2=6

x1=(-4)

Rewrite the problem down.

[tex]\sf{\left(\dfrac{6-4}{2},\:\dfrac{-10+16}{2}\right)}[/tex]

Solve.

6-4=2

2/2=1

-10+16=6

6/2=3

= (1,3)

Therefore, the correct answer is B (1,3).

I hope this helps, let me know if you have any questions.

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determine the rate of change for the right side of…

Answers

Answer:

Decreasing at an increasing rate

Step-by-step explanation:

graph looks like an arch

right side is going down

right side is going down as x increases

Katie is planning to paint the gate of her house that has a glass panel. Painting the gate costs $4 per square foot. How much will she have to spend to paint the gate?

Answers

Answer:

$14.15

Step-by-step explanation:

6+4+.75+.4

Burger Barn makes a dipping sauce by mixing 4 spoonfuls of honey with 1 spoonful of mustard. Sandwich Town makes a dipping sauce by mixing 8 spoonfuls of honey with 2 spoonfuls of mustard

Which dipping sauce has a stronger mustard flavor?

Answers

The dipping sauce which has a stronger mustard flavor between burger barn and be sandwich town is burger barn

Ratio

Burger bun:

Honey = 4 spoonfulsMustard = 2 spoonfuls

Mustard : honey

= 2 : 4

= 2/4

= 1/2

= 0.5

Sandwich:

Honey = 8 spoonfulsMustard = 2 spoonfuls

Mustard : honey

= 2 : 8

= 2/8

= 1/4

= 0.25

Therefore, burger barn has a more stronger mustard flavor of dipping sauce between burger barn and be sandwich town.

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Answer:

Step-by-step explanation:

The two dipping sauce have same taste.

Simplify the expression below.
2^3 x 2^2
A.46
B. 45
C. 25
D. 26

Answers

Answer: 32 is the answer to the expression you provided.

Step-by-step explanation:

[tex]2^3\times2^2\\2\times2\times2\times2\times2\\4\times4\times2\\16\times2\\\rightarrow32[/tex]

[tex]\huge\text{Hey there!}[/tex]


[tex]\huge\boxed{E}\textsf{quation:}[/tex]

[tex]\mathsf{2^3 \times 2^2}[/tex]


[tex]\huge\boxed{S}\textsf{olving:}[/tex]

[tex]\mathsf{2^3 \times 2^2}[/tex]

[tex]\mathsf{= 2\times2\times2 \times2\times2}[/tex]

[tex]\mathsf{= 4\times4\times2}[/tex]

[tex]\mathsf{= 16\times2}[/tex]

[tex]\mathsf{= 32}[/tex]


[tex]\huge\boxed{T}\textsf{herefore, your answer should be:}[/tex]

[tex]\huge\boxed{\frak{32}}\huge\checkmark[/tex]

[tex]\huge\text{Good luck on your assignment \& enjoy your day!}[/tex]


~[tex]\frak{Amphitrite1040:)}[/tex]

Sketch a graph of the following rational function: h(x)= x²-1/ x³-2x²-x+2​

Answers

Note that

[tex]\frac{x^2-1}{x^3 - 2x^2 -x+2}=\frac{x^2 -1}{x^2 (x-2)-(x-2)}=\frac{x^2 -1}{(x^2 -1)(x-2)}[/tex]

So, for all [tex]x \neq \pm 1[/tex], [tex]f(x)=\frac{1}{x-2}[/tex].

So, the graph looks like something like as following in the image.

The volume of the square-based pyramid shown is 72 m³. If the area of its
base is 36 m2, what is the height (h) of the pyramid?
base,

Answers

Answer:

Height = 6m

Step-by-step explanation:

[tex]\frac{1}{3}[/tex] × 36 = 12

72 ÷ 12 = 6

It’s the start of a new football season and my favorite team, the WACO Hawks, is looking good! They won their first
game by beating Dublin Irish 28-27 on a last second play.
In the course of the game they piled up a lot of running yards, divided among four players:
• The bruising fullback, Vernon Variable, accounted for a chuck of those yards.
• The star halfback, Reggie Root, ran for 15 less than three times as many yards as Vernon did.
• The speedy wide-out, Larry Linear, only ran once but he picked up 11 more yards than Vernon’s total on that
play, a fancy reverse that went for a touchdown.
• The crafty quarterback, Quentin Quadratic, ran for a total of 18 yards on a variety of scrambles.
If the WACO Hawks ran for 229 yards, how many yards did each of the four players gain? Remember to define a
variable, write an equation, and explain your work (focusing on the why you did what you did)

Answers

Vernon Variable ran 43 yards, Reggie Root ran 114 yards, Larry Linear ran 54 yards, and Quentin ran 18 yards.

How to solve Linear Equations Word Problems?

We are told that the total number of yards the WACO Hawks ran is 229. Thus, we can say that: W = 229

Now, we know that Vernon Variable gained many yards. Thus, the amount of yards will be indicated by "V"

Now, Reggie Root ran for 15 less than three times as many yards as Vernon did. Thus, distance Reggie root ran is represented by;

R = 3V-15

Larry Linear picked up 11 more yards than Vernon’s total. Thus, total yards by Larry Linear is: L = V + 11

Quentin Quadratic ran a total of 18 yards. Thus; Q=18.

Now, all of the player's totals add up make what the total team ran. Thus, the expression is;

V + 3V - 15 + V + 11 + 18 = 229

Simplifying this gives;

5V + 14 = 229

5V + 14 = 229

Subtract 14 from both sides to get;

5V = 215

Divide both sides by 5 to get;

V = 43

Thus, Vernon ran a total of 43 yards.

Total run by Reggie is:

R = 3(43) -15

R = 129 - 15

R = 114 yards.

Total run by Larry:

L = V + 11

L = 43 + 11

L = 54 yards.

Thus, we conclude that Vernon Variable ran 43 yards, Reggie Root ran 114 yards, Larry Linear ran 54 yards, and Quentin ran 18 yards.

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Find the area of the shaded region. Round the answer to the nearest
tenth decimal place.

Answers

[tex] \qquad \qquad \bf \huge\star \: \: \large{ \underline{Answer} } \huge \: \: \star[/tex]

Area of shaded region = 2571.66 in²

[tex]\textsf{ \underline{\underline{Steps to solve the problem} }:}[/tex]

Radius of smaller circle = 25 in

Radius of larger circle = 25 + 13 = 38 in

Area of ring : Area of larger circle - Area of smaller circle

[tex]\qquad❖ \: \sf \:\pi {(38)}^{2} - \pi {(25)}^{2} [/tex]

[tex]\qquad❖ \: \sf \:\pi( {38}^{2} - 25 {}^{2} )[/tex]

[tex]\qquad❖ \: \sf \:3.14(1444 - 625)[/tex]

[tex]\qquad❖ \: \sf \:3.14(819)[/tex]

[tex]\qquad❖ \: \sf \:2571.66 \: \: in {}^{2} [/tex]

[tex] \qquad \large \sf {Conclusion} : [/tex]

Area = 2571.66 in²

A fair coin is flipped seven times. what is the probability of the coin landing tails up at least two times?

Answers

The required probability of the coin landing tails up at least two times is 15/16.

Given that,
A fair coin is flipped seven times. what is the probability of the coin landing tails up at least two times is to be determined.

What is probability?

Probability can be defined as the ratio of favorable outcomes to the total number of events.

Here,
In the given question,
let's approach inverse operation,
The probability of all tails  = 1 / 2^7 because there is only one way to flip these coins and get no heads.
The probability of getting 1 head = 7 /2^7
Adding both the probability = 8 / 2^7
Probability of the coin landing tails up at least two times = 1 - 8/2^7
                                                                                     = 1 - 8 / 128
                                                                                     = 120 / 128
                                                                                     = 15 / 16

Thus, the required probability of the coin landing tails up at least two times is 15/16.

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The simple interest on certain principal is 1/2 of the amount in 5years. find the rate of interest

Answers

Answer:

10

Step-by-step explanation:

Quick algebra 1 question for 25 points!

Only answer if you know the answer, Tysm!

Answers

By using the linear function which models the data in the given table, if x = 2, then y is approximately: A. -11.

What is a scatter plot?

A scatter plot can be defined as a type of graph which is used for the graphical representation of the values of two variables, with the resulting points showing any association (correlation) between the data set.

What is a linear function?

A linear function can be defined as a type of function whose equation is graphically represented by a straight line on the cartesian coordinate.

By critically observing the graph (see attachment) which models the data in the given table, we can infer and logically deduce that the linear function is given by:

y = -5.9245x + 0.9958

If x = 2, then y is approximately:

y = -5.9245(2) + 0.9958

y = -11.849 + 0.9958

y = -10.8532 ≈ -11.

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At the city museum, child admission is $6.20 and adult admission is $9.40. On Thursday, 163 tickets were sold for a total sales of $1221.80. How many adult
tickets were sold that day?

Answers

Systems of Equations

To form a system of equation from a word problem, we must recognize different variables to form different equations.

Solving the Question

Let a represent the number of child tickets.

Let b represent the number of adult tickets.

We're given:

1a = $6.201b = $9.40a and b in total is 163Total sales = $1221.80

Because we're given that a and b in total is 163, we can form the following equation:

[tex]a+b=163[/tex]

We're also given that the total sales made is $1221.80. Because we know that 1a = $6.20 and 1b = $9.40, we can also form the following equation:

[tex]6.2a+9.4b=1221.8[/tex]

Here are our two equations:

[tex]a+b=163[/tex]

[tex]6.2a+9.4b=1221.8[/tex]

Solving the System of Equations

We can solve using the method of elimination. Multiply both sides by 6.2 in the first equation:

[tex]6.2(a+b)=6.2(163)\\6.2a+6.2b=1010.6[/tex]

Subtract this new equation from the second equation to cancel out a:

[tex]\hspace{10}6.2a+9.4b=1221.8\\- 6.2a+6.2b=1010.6\\\rule{100}{0.5}\\3.2b=211.2[/tex]

Solve for b:

[tex]b=66[/tex]

Therefore, the number of adult tickets sold is 66.

Answer

66

HEY PLS HELP IM STUCK

Answers

Answer:16

Explanation:To find X intercept you plus in zero for X since X intercept is the value that the line touches the X axis so knowing this

-2x+8(0)=-32

-2x=-32

-32/-2

X=16

PLEASE HELP IM STUCK

Answers

Answer:

y = -3x + 1

Step-by-step explanation:

First, we can find the slope of the line.

The slope is (change in y)/(change in x).

We can use the points that are marked in orange: (0,1) and (1,-2)

The change in y is 1 to -2, which is -3.

The change in x is 0 to 2, which is 1.

The slope will be -3/1, which is also: -3.

We have y = -3x + b currently.

The b is the y-intercept, meaning (the point that touches the y axis, the vertical line).

The point (0,1) touches the y-intercept, so b will be 1.

We can finish our equation as: y = -3x + 1

The area of a circle of radius 10 units is equal to the surface area of a sphere of radius 5 units.
A. True
B.False

Answers

Answer:  True

Explanation:

The area of the circle with radius 10 is...

A = pi*r^2

A = pi*10^2

A = 100pi

The surface area of the sphere with radius 5 is...

SA = 4pi*r^2

SA = 4pi*5^2

SA = 100pi

Both results are the same, so the claim is true. We can think of surface area as the amount of wrapping paper needed to cover the sphere.

Nick wrote the function p(x) = 17 + 42x – 7x2 in vertex form. His work is below.

p(x) = –7x2 + 42x + 17
p(x) = –7(x2 – 6x) + 17
(StartFraction negative 6 Over 2 EndFraction) squared = 9; p(x) = –7(x2 – 6x + 9) + 17
p(x) = –7(x – 3)2 + 17
When Nick checked his work it did not match the standard form function. Analyze Nick’s work. What was his mistake?

In step 1, he did not put the function in standard form correctly.
In step 2, he should have also factored –7 from the constant term, 17.
In step 3, he did not subtract –7(9) to keep the function equivalent.
In step 4, he did not write the perfect square trinomial correctly as a binomial squared.

Answers

Answer:

step 3

Step-by-step explanation:

he should have subtracted 9 to the outside.

whatever you do to the inside you must do to the opposite to the outside

so your final form must be -7(x-3)^2 + 8

its really confusing ​

Answers

Answer:

Step-by-step explanation:

6:1 i think

9385848384757382810394584828184757463737474

find the prime factorization of 11250

Answers

Answer:

2 x 3 x 3 x 5 x 5 x 5 x 5

Step-by-step explanation:

see picture

If it costs susan $25 to rent a truck for 1 hour and $100 to rent a truck for 4 hours, how much will it cost for her to rent a truck for her entire 8-hour work day? a. $150 b. $200 c. $225 d. $250

Answers

Answer:  $200  (choice B)

Explanation:

Notice that 100/4 = 25 which matches with the fact the cost is $25 per hour.

Therefore, 8 hours will yield a total cost of 8*25 = 200 dollars

The cost for Susan to rent a truck for her entire 8-hour work day is $200. Therefore, option B is the correct answer.

Given that, if it costs Susan $25 to rent a truck for 1 hour and $100 to rent a truck for 4 hours.

What is the unitary method?

The unitary method is a technique for solving a problem by first finding the value of a single unit, and then finding the necessary value by multiplying the single unit value.

Cost of rent of truck for 8 hours = 1 hour rent × Number of hours

= 25 × 8

= $200

The cost for Susan to rent a truck for her entire 8-hour work day is $200. Therefore, option B is the correct answer.

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Students are measuring various objects around the classroom. A pencil measures 8 ⅜ inches while a pair of scissors measures 5 ½ inches. How much longer is the pencil than the pair of scissors?

Answers

The pencil is longer than the pair of scissors by  [tex]2\frac{7}{8}[/tex] inches.

A pencil measures  [tex]8\frac{3}{8}[/tex]  inches.

A pair of scissors measures  [tex]5\frac{1}{2}[/tex]  inches.

We need to find the difference between the measures of a pencil and the scissors.

We see that the pencil measure is greater than the pair of scissors.

What is a mix fraction?

A fraction is a part of a whole number. It has two parts - numerator and denominator.

Example: If you cut a cake into three slices each slice is 1/3.

Where 1 = numerator and 3 = denominator.

Four types of fractions:

Unit fraction - when the numerator is 1.

Proper fraction - When the numerator is less than the denominator.

Improper fraction - When the numerator is greater than the denominator.

Mixed fraction - When the fraction contains a whole number with a proper fraction.

Example:  [tex]3\frac{1}{3}[/tex]

The given measure of the pen and the pair of scissors is in mix fraction.

The pencil measure is longer than the pair of scissors measure so,

We will subtract the measure of the pair of scissors from the measure of the pen.

We have,

       =  [tex]8\frac{3}{8} - 5\frac{1}{2}[/tex]

We can write the mix fraction into an improper fraction.

We multiply the denominator with the whole number and add this product with the numerator to get our numerator of the improper fraction. The denominator will remain the same as the mix fraction in the improper fraction.

So,

[tex]8\frac{3}{8}=\frac{(8\times8)+3}{8}=\frac{64 + 3}{8} = \frac{67}{8}\\ 5\frac{1}{2} =\frac{(5\times2)+1}{2}= \frac{(10+1)}{2} = \frac{11}{2}[/tex]

= 67/8 - 11/2

= (67-44) / 8

= 23 / 8

Writing in mix fraction.

=  [tex]2\frac{7}{8}[/tex]

Thus the pencil is longer than the pair of scissors by  [tex]2\frac{7}{8}[/tex] inches.

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Quick algebra 1 question for 10 points!

Only answer if you know the answer, quick shout-out to tariqareesha2 and MrBrainly, tysm for the help!

Answers

[tex]y = - 5x + n \\ [/tex]

( -1 , -2 ) satisfies the equation of y

[tex] - 2 = - 5( - 1) + n \\ - 2 = 5 + n \\ n = - 7[/tex]

[tex]y = - 5x - 7 \\ 5x + y = - 7[/tex]

Option 2

Answer:

○ [tex]5x + y = -7[/tex]

Step-by-step explanation:

The formula for forming the equation of a line given a point and a slope is:

[tex]\boxed{y- y_1 = m(x - x_1)}[/tex],

where:

m = slope (-5)

[tex]y_1[/tex] = y-coordinate of point (-2)

[tex]x_1[/tex] = x-coordinate of point (-1).

Substituting these values into the formula:

[tex]y - (-2) = -5(x - (-1))[/tex]

⇒ [tex]y + 2 = -5(x + 1)[/tex]

⇒ [tex]y + 2 = -5x -5[/tex]      [expanding the brackets]

⇒ [tex]y = -5x -5 - 2[/tex]      [subtracting 2 from both sides]

⇒ [tex]y = -5x - 7[/tex]

⇒ [tex]5x + y = -7[/tex]            [adding [tex]5x[/tex] to both sides]

This means that the second option is correct.

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help!! what do i do?!?

Answers

Answer is A. None of these.
Reason is Quadratic and exponential graphs are both curved lines. Linear means straight line which this is not a straight line, it has two or more slopes.

Question is in image below:

Answers

The sinusoidal equation will be Y=4.25 sin[(π/26)(t-11)]+12.25

How to compute the equation?

The following can be deduced:

Function Y=Asin(wt-Φ)+β

Amplitude A=(16.5-8)/2=4.25 hours

Vertical shift  β= (16.5+8)/2=12.25

Period is 52 weeks, thus 52=2π/ω→ω=2π/52=π/26

The phase shift Φ can be gotten if we divide the whole year in 4 sub-intervals each interval would be :

[0,13], [13,26],[26,39],[39,52]

The summer solstice occurs at the end of week 24.

The winter solstice occurs at the end of week 51.

The maximum of sine function happens at the end of the first sub-interval [0,13]

Here, Φ is 11, thus, the function would be

Y=4.25 sin[(π/26)(t-11)]+12.25.

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What is the slope of the line that passes through the points (1, 1) and (4, 4)?
Write your answer in simplest form.

Answers

Answer:

The answer is 1

Step-by-step explanation:

Formula for finding the slope: [tex]\frac{y2-y1}{x2-x1}[/tex]

Take y2 and y1 from (4,4) (1,1)

Take x2 and x1 from (4,4) (1,1)

[tex]\frac{y2-y1}{x2-x1} = \frac{4-1}{4-1} = \frac{3}{3} = 1[/tex]

This is how the answer is 1

Hope it helps :)

A polynomlal function has x-Intercepts at -2, ;, and 2 and a relative maximum at x=-1. graph Which graph matches the description of this function?

Answers

The graph that matches the polynomial function that has x-Intercepts at -2, ;, and 2 and a relative maximum at x = -1 is: graph A.

How to Determine the Graph of a Polynomial Function?

We are given that the polynomial function has the following characteristics:

Relative maximum at x = -1, this implies that the peak point of the graph has an x-value that is equal to -1. In order words, the "mountain" is at x = -1.

Graph A has a "mountain" that is at x = -1.

We are given the x-intercepts of the polynomial function as:

-2, 1/2, and 2. This means that the graph intercepts the x-axis at -2, 1/2, and 2.

Graph A in the image attached has x-intercepts of -2, 1/2, and 2.

Therefore, we can conclude that the graph that matches the polynomial function that has x-Intercepts at -2, ;, and 2 and a relative maximum at x = -1 is: graph A.

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The question is down below. Which option i correct?

Answers

Answer:

Step-by-step explanation:

overall the answer is wrong i say it is the first one  

Answer:

The first one is theost plausible because root 16 is 4, 30 + 4 is 34, the actual answer is 25.38

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