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-4x+y=6
-5x-y+21
solve for x and y

User JayJay
by
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1 Answer

2 votes

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Answer:

(x, y) = (-3, -6)

Explanation:

The coefficients of y are opposites, so adding the two equations will cancel the y-terms.

(-4x +y) +(-5x -y) = (6) +(21)

-9x = 27 . . . . . simplify

x = -3 . . . . . . divide by -9

Now, we can find y.

-4(-3) +y = 6 . . . . . substitute for x in the first equation

y = 6 -12 = -6 . . . . subtract 12

The solution is (x, y) = (-3, -6).

-4x+y=6 -5x-y+21 solve for x and y-example-1
User Chronio
by
7.0k points
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