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3 years ago

Which is the answer and how did you solve it?

Mathematics

1 answer:

motikmotik3 years ago

3 0

Its pretty simple

9x-7y = 22
x + 3y = -24

(9x-7y = 22)
-9(x + 3y = -24)
= -9x -27y = 216
+ 9x-7y = 22
= -34y = 238
= / -34 = 238/-34
y = -7

now plug -7 in one of the equation
x + 3(-7) = -24
x -21 = -24
+21. +21
x = -3

so answer is x = -3 and y = -7

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