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3 years ago

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

Mathematics

1 answer:

Reil [10]3 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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aₙ₊₁/aₙ =

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