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3 years ago

My test scores have been 85,80,95 and 65. What must I earn on my next test to have a mean score of at least 80. Please show work

Mathematics

1 answer:

OverLord2011 [107]3 years ago

3 0

Hope that helps! Let me know if you’d like me to clarify something :)

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Q3: Identify the graph of the equation and write and equation of the translated or rotated graph in general form. (Picture Provi

natta225 [31]

Answer:

b. circle; $2(x')^2+2(y')^2-5x'-5\sqrt{3}y'-6 =0$

Step-by-step explanation:

The given conic has equation;

$x^2-5x+y^2=3$

We complete the square to obtain;

$(x-\frac{5}{2})^2+(y-0)^2=\frac{37}{4}$

This is a circle with center;

$(\frac{5}{2},0)$

This implies that;

$x=\frac{5}{2},y=0$

When the circle is rotated through an angle of $\theta=\frac{\pi}{3}$ ,

The new center is obtained using;

$x'=x\cos(\theta)+y\sin(\theta)$ and $y'=-x\sin(\theta)+y\cos(\theta)$

We plug in the given angle with x and y values to get;

$x'=(\frac{5}{2})\cos(\frac{\pi}{3})+(0)\sin(\frac{\pi}{3})$ and $y'=--(\frac{5}{2})\sin(\frac{\pi}{3})+(0)\cos(\frac{\pi}{3})$

This gives us;

$x'=\frac{5}{4} ,y'=\frac{5\sqrt{3} }{4}$

The equation of the rotated circle is;

$(x'-\frac{5}{4})^2+(y'-\frac{5\sqrt{3} }{4})^2=\frac{37}{4}$

Expand;

$(x')^2+(y')^2-\frac{5\sqrt{3} }{2}y'-\frac{5}{2}x'+\frac{25}{4} =\frac{37}{4}$

Multiply through by 4; to get

$4(x')^2+4(y')^2-10\sqrt{3}y'-10x'+25 =37$

Write in general form;

$4(x')^2+4(y')^2-10x'-10\sqrt{3}y'-12 =0$

Divide through by 2.

$2(x')^2+2(y')^2-5x'-5\sqrt{3}y'-6 =0$

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3 years ago

The perimeter of a square depends on the length of its sides. Answer the questions below regarding the relationship between the

Alexxandr [17]

The independent variable, x, represents the SIDE LENGTHS, and the dependent variable is the PERIMETER, because the PERIMETER, depends on the SIDE LENGTHS.

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4 years ago

Help me answer this question people will give brainliest

lana66690 [7]

Answer:It'll be part B

Step-by-step explanation:

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3 years ago

If 4 T-shirts cost $15, how much will 12 T-shirts cost?

tatuchka [14]

Answer: $45

Step-by-step explanation:

15/4 = 3.75

Each shirt costs $3.75

3.75 * 12 = 45

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3 years ago

Read 2 more answers

Let U = {1, 2, 3, 4, 5, 6, 7), A = {2, 4, 6, 7), and B = {1, 4, 7}. Find the set (A U B)'.

den301095 [7]

Step-by-step explanation:

(A U B) = {1,2, 4, 6, 7}

(A U B)'= U- (A U B) = { 3,5}<------- Answer

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3 years ago