15. Find the value(s) of the variable(s). If necessary, round decimal answers to the nearest
tenth.
52
X
13

Answer:

7)Bagel costs $3.5 and muffin cost $1.25

8) Ticket is $9 while snacks are $2

9) Correct because left hand side is zero

10) Correct because they both have same slope and same y-intercept

Step-by-step explanation:

7) Let bagel be x and muffin be y.

Thus;

For Aaron;

x + 3y = 7.25 - - - (1)

For bee;

x + 2y = 6 - - - (2)

Subtract eq 2 from eq 1 to get;

y = 1.25

Put 1.25 for y in eq 2;

x + 2(1.25) = 6

x + 2.5 = 6

x = 6 - 2.5

x = 3.5

Bagel costs $3.5 and muffin cost $1.25

8) Let movie ticket be x and snacks be y.

Thus;

2x + 3y = 24 - - - (1)

3x + 4y = 35 - - - (2)

Multiply eq(1) by 3 and eq(2) by 2 to get;

6x + 9y = 72 - - - (3)

6x + 8y = 70 - - - (4)

Subtract eq 4 from eq 3 to get;

y = 2

Put 2 for y in eq 3;

6x + 9(2) = 72

6x + 18 = 72

6x = 72 - 18

6x = 54

x = 54/6

x = 9

Ticket is $9 while snacks are $2

9) using elimination, subtract eq 1 from eq 2, we will see that the entire left hand side is equal to zero.

Thus, no solution exists because we can't isolate the variable to get an answer.

10) The answer is correct because for a system of 2 simultaneous equations to have infinite solutions, they both have to have the same y-intercept and also same slope.

In this case, their y-intercept which is when x is 0 is;

3(0) + y = 9

y = 9

Their slope is also the same equal to 3.

Answer:

1/2

Step-by-step explanation:

The slope can be found by looking at the Rise over run or in other words how ever much it moves up over how much it move right.

Answer:

The athlete jogged at 4 miles per hour for 30 minutes, and jogged at 6 miles per hour for 1 hour.

Step-by-step explanation:

Given that at first an athlete jogs at 4 miles per hour and then jogs at 6 miles per hour, traveling 8 miles in 1.5 hours, to determine how long does the athlete jogs at each speed the following calculation must be performed:

4 x 1.5 + 6 x 0 = 6

4 x 1 + 6 x 0.5 = 7

4 x 0.75 + 6 x 0.75 = 7.5

4 x 0.5 + 6 x 1 = 8

Therefore, the athlete jogged at 4 miles per hour for 30 minutes, and jogged at 6 miles per hour for 1 hour.

Answer:

ok

Step-by-step explanation:

I think

Answer:

(a): Marginal pmf of x

[tex]P(0) = 0.72[/tex]

[tex]P(1) = 0.28[/tex]

(b): Marginal pmf of y

[tex]P(0) = 0.81[/tex]

[tex]P(1) = 0.19[/tex]

(c): Mean and Variance of x

[tex]E(x) = 0.28[/tex]

[tex]Var(x) = 0.2016[/tex]

(d): Mean and Variance of y

[tex]E(y) = 0.19[/tex]

[tex]Var(y) = 0.1539[/tex]

(e): The covariance and the coefficient of correlation

[tex]Cov(x,y) = 0.0468[/tex]

[tex]r \approx 0.2657[/tex]

Step-by-step explanation:

Given

x = bottles

y = carton

See attachment for complete question

Solving (a): Marginal pmf of x

This is calculated as:

[tex]P(x) = \sum\limits^{}_y\ P(x,y)[/tex]

So:

[tex]P(0) = P(0,0) + P(0,1)[/tex]

[tex]P(0) = 0.63 + 0.09[/tex]

[tex]P(0) = 0.72[/tex]

[tex]P(1) = P(1,0) + P(1,1)[/tex]

[tex]P(1) = 0.18 + 0.10[/tex]

[tex]P(1) = 0.28[/tex]

Solving (b): Marginal pmf of y

This is calculated as:

[tex]P(y) = \sum\limits^{}_x\ P(x,y)[/tex]

So:

[tex]P(0) = P(0,0) + P(1,0)[/tex]

[tex]P(0) = 0.63 + 0.18[/tex]

[tex]P(0) = 0.81[/tex]

[tex]P(1) = P(0,1) + P(1,1)[/tex]

[tex]P(1) = 0.09 + 0.10[/tex]

[tex]P(1) = 0.19[/tex]

Solving (c): Mean and Variance of x

Mean is calculated as:

[tex]E(x) = \sum( x * P(x))[/tex]

So, we have:

[tex]E(x) = 0 * P(0) + 1 * P(1)[/tex]

[tex]E(x) = 0 * 0.72 + 1 * 0.28[/tex]

[tex]E(x) = 0 + 0.28[/tex]

[tex]E(x) = 0.28[/tex]

Variance is calculated as:

[tex]Var(x) = E(x^2) - (E(x))^2[/tex]

Calculate [tex]E(x^2)[/tex]

[tex]E(x^2) = \sum( x^2 * P(x))[/tex]

[tex]E(x^2) = 0^2 * 0.72 + 1^2 * 0.28[/tex]

[tex]E(x^2) = 0 + 0.28[/tex]

[tex]E(x^2) = 0.28[/tex]

So:

[tex]Var(x) = E(x^2) - (E(x))^2[/tex]

[tex]Var(x) = 0.28 - 0.28^2[/tex]

[tex]Var(x) = 0.28 - 0.0784[/tex]

[tex]Var(x) = 0.2016[/tex]

Solving (d): Mean and Variance of y

Mean is calculated as:

[tex]E(y) = \sum(y * P(y))[/tex]

So, we have:

[tex]E(y) = 0 * P(0) + 1 * P(1)[/tex]

[tex]E(y) = 0 * 0.81 + 1 * 0.19[/tex]

[tex]E(y) = 0+0.19[/tex]

[tex]E(y) = 0.19[/tex]

Variance is calculated as:

[tex]Var(y) = E(y^2) - (E(y))^2[/tex]

Calculate [tex]E(y^2)[/tex]

[tex]E(y^2) = \sum(y^2 * P(y))[/tex]

[tex]E(y^2) = 0^2 * 0.81 + 1^2 * 0.19[/tex]

[tex]E(y^2) = 0 + 0.19[/tex]

[tex]E(y^2) = 0.19[/tex]

So:

[tex]Var(y) = E(y^2) - (E(y))^2[/tex]

[tex]Var(y) = 0.19 - 0.19^2[/tex]

[tex]Var(y) = 0.19 - 0.0361[/tex]

[tex]Var(y) = 0.1539[/tex]

Solving (e): The covariance and the coefficient of correlation

Covariance is calculated as:

[tex]COV(x,y) = E(xy) - E(x) * E(y)[/tex]

Calculate E(xy)

[tex]E(xy) = \sum (xy * P(xy))[/tex]

This gives:

[tex]E(xy) = x_0y_0 * P(0,0) + x_1y_0 * P(1,0) +x_0y_1 * P(0,1) + x_1y_1 * P(1,1)[/tex]

[tex]E(xy) = 0*0 * 0.63 + 1*0 * 0.18 +0*1 * 0.09 + 1*1 * 0.1[/tex]

[tex]E(xy) = 0+0+0 + 0.1[/tex]

[tex]E(xy) = 0.1[/tex]

So:

[tex]COV(x,y) = E(xy) - E(x) * E(y)[/tex]

[tex]Cov(x,y) = 0.1 - 0.28 * 0.19[/tex]

[tex]Cov(x,y) = 0.1 - 0.0532[/tex]

[tex]Cov(x,y) = 0.0468[/tex]

The coefficient of correlation is then calculated as:

[tex]r = \frac{Cov(x,y)}{\sqrt{Var(x) * Var(y)}}[/tex]

[tex]r = \frac{0.0468}{\sqrt{0.2016 * 0.1539}}[/tex]

[tex]r = \frac{0.0468}{\sqrt{0.03102624}}[/tex]

[tex]r = \frac{0.0468}{0.17614266944}[/tex]

[tex]r = 0.26569371378[/tex]

[tex]r \approx 0.2657[/tex] --- approximated

Answer:

$320

Step-by-step explanation:

400*0.8(decimal form of 80%) = 320

Answer:$80

Step-by-step explanation:

$400x0.80=$320 off

400-320=$80

Or

$400 x 0.20= $80 sale price

Answer: 5.8%

Step-by-step explanation: got it right lol

Answer:

-6, 10

Step-by-step explanation:

When you reflect of the y-axis the x will be negative if the original point was positive and the y will stay the same

Answer:

1/4 of 0.25

Step-by-step explanation:

2/4 x 2/4 = 1/4

Answer:

18 because of its addition

Step-by-step explanation:

πr²=3+2+7+2+2+2

=5+9+4

=18

Answer:

z = 166°

Step-by-step explanation:

Given:

x = 89

y = 12

An angle with its vertex in a circle = ½(intercepted arcs)

Thus:

x = ½(y + z)

Substitute

89 = ½(12 + z)

Multiply both sides by 2

2(89) = 12 + z

178 = 12 + z

178 - 12 = z

z = 166°

Answer:

The answer is C

Step-by-step explanation:

If you plot them carefully.

Answer:

17.27

Step-by-step explanation:

so we do 5.5/2=2.75

2x3.14= 6.28

6.28x2.75=17.27

Answer:

1 and 4

or say it as

More seventh graders prefer art class to music class as an elective

There is no association between a student's grade level and the electives they prefer

Answer: B rational

Step-by-step explanation:

Answer:

48 π

Step-by-step explanation:

Area of Circle =πr∧2

Big Circle Area = π(8)∧2 = 64π

Small Circle Area =π(4)∧2= 16π

Shaded Region = 64π - 16π = 48π

Answer:

40

explanation:

The range is the difference between the smallest and highest numbers in a list or set. To find the range, first put all the numbers in order. Then subtract the lowest number from the highest. The answer gives you the range of the list.

Answer:

82+2>34

84>34

True

I hope this helps :)

Answer:

No they do not.

5/18 ≠ 1/2

If it did, it would be 9/18

Hope that helps!

Step-by-step explanation:

Answer:

58.9

Step-by-step explanation:

y²=x²+z²-2×z cos(y)

20²=22²+18²-2(22)(18) cos (y)

400=484+324-792 cos(y)

-408=-772 cos (y)

408/792=cos y

y=cos⁻¹(408/792)=58.9

hope it helps...

have a great day!!

Answer:

40 because every hour he charges 40 dollas so its 40x+75=y

Step-by-step explanation:

The slope is 40 because every hour he charges 40 dollars so its 40x+75=y

We have given that,

An electrician charges $40 per hour plus an initial service fee of $75. He charges a customer $195 for 3 hours of work.

We have to determine,

When this linear relationship is graphed, which value represents the slope.

The slope of a line is a measure of its steepness. Mathematically, the slope is calculated as a rising overrun.

The slope is 40 because every hour he charges 40 dollars so its 40x+75=y

To learn more about slope visit:

https://brainly.com/question/3493733

#SPJ2

Answer:

The solution to this question is 104.25cm²

Step-by-step explanation:

u

Answer:

hi

Step-by-step explanation:

i think so

A=

[tex] = \pi \times {r}^{2} [/tex]

=3,14×5,76²=104,177

hope it helps

have a nice day

Given:

The point P = (3,2) is rotated 270° counterclockwise about the origin.

To find:

The image of the given point after rotation.

Solution:

If a point rotated 270° counterclockwise about the origin, then the rule of rotation is:

[tex](x,y)\to (y,-x)[/tex]

Using this rule, we get

[tex]P(3,2)\to P'(2,-3)[/tex]

Therefore, the image of given point P = (3,2) after the rotation of 270° counterclockwise about the origin, is P'(2,-3).

Answer:

g(5n)=5n^2+4

Step-by-step explanation:

Substitute 5n for x

5n^2+4

You can't really do much with this so that is the answer

Answer:

Verified below

Step-by-step explanation:

We want to show that (Cos2θ)/(1 + sin2θ) = (cot θ - 1)/(cot θ + 1)

In trigonometric identities;

Cot θ = cos θ/sin θ

Thus;

(cot θ - 1)/(cot θ + 1) gives;

((cos θ/sin θ) - 1)/((cos θ/sin θ) + 1)

Simplifying numerator and denominator gives;

((cos θ - sin θ)/sin θ)/((cos θ + sin θ)/sin θ)

This reduces to;

>> (cos θ - sin θ)/(cos θ + sin θ)

Multiply top and bottom by ((cos θ + sin θ) to get;

>> (cos² θ - sin²θ)/(cos²θ + sin²θ + 2sinθcosθ)

In trigonometric identities, we know that;

cos 2θ = (cos² θ - sin²θ)

cos²θ + sin²θ = 1

sin 2θ = 2sinθcosθ

Thus;

(cos² θ - sin²θ)/(cos²θ + sin²θ + 2sinθcosθ) gives us:

>> cos 2θ/(1 + sin 2θ)

This is equal to the left hand side.

Thus, it is verified.

Answer:

A- point A

Step-by-step explanation:

Absolute value doesnt care about the sign so a negative is a positive.

PLease Brainliest

Answer:

parallel y=7x+26

perpendicular y=1/7x+32/7

Step-by-step explanation:

parallel line have the same slope

y-5=7(x-(-3))

y-5=7(x+3)

y-5=7x+21

y=7x+21+5

y=7x+26

perpendicular slope  is the opposite of the original slope of 7

y-5=-1/7(x-(-3))

y-5=-1/7(x+3)

y-5=-1/7x-3/7

y=-1/7x-3/7+5

y=-1/7x+32/7

Answer:

6.99 rounded up to 7 :))

Step-by-step explanation:

1/3 = 0.33

2.33 * 3 = 6.99 ft