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2 years ago

-3y -9x =21. -18x +4y =32

Mathematics

1 answer:

Reil [10]2 years ago

5 0

The value of x is -2 and the value of y is -1.

Step-by-step explanation:

Step 1; The given equations are taken as

-3y -9x =21 or -9x -3y = 21, take this as equation 1

-18x +4y =32, take this as equation 2

Step 2; We multiply equation 1 with 2 and equation 2 with 1 so we can cancel out the variable x in both equations. By doing this we get

-18x -6y =42, take this as equation 3

-18x +4y =32, this is the same as equation 2

If we subtract 3 with 2, we cancel out the x variable and can calculate the value of y.

10y = -10 , y = -10/10 = -1

Step 3; Substituting this value of y in any of the previous equations we will get x's value. Here this value of y is substituted in equation 2.

-18x +4(-1) =32, -18x -4 = 32 , -18x = 36, x=-2.

So we have x = -2 and y = -1.

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Troyanec [42]

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Step-by-step explanation:

Step 1:

The given composite shape is made up of a cube with a side length of 5 inches and a cylinder with a radius of 2 inches and a height of 4 inches.

The surface area of the composite shape is given by summing the individual surface areas.

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Step 2:

Any cube's surface area is calculated by multiplying 6 with the square of the side length ( $a^2$ ).

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Step 3:

Any cylinder's surface area is calculated with the following formula;

The cylinder's surface area = $2 \pi r h+2 \pi r^{2}$ = $2 \pi (2) (4)+2 \pi (2)^{2}$ = $75.398$ square inches

Step 4:

The composite shape's surface area = The cube's surface area + the cylinder's surface area.

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3 0

2 years ago

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Naily [24]

Answer:

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Step-by-step explanation:

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1 year ago

You have 5 cups of birdseed. You use 3/5, cup of birdseed each day. How many days will your birdseed last?

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2 years ago

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Ne4ueva [31]

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2 years ago

Read 2 more answers

You deposit $300 in a savings account. The account earns 2% simple interest per year. What is the interest and balance earned af

kenny6666 [7]

Answer:

$365.70

Step-by-step explanation:

The formula to find this is $y = a(1+r)^t\\$

For this, a is the initial amount, r is the growth rate percentage (but displayed as a decimal), and t is time.

So to solve, you would do

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2 years ago