4 years ago

Solve using substitution. x + 3y = -13 5x + 7y = -9

1 answer:

6 0

From equation 1
x = -3y-13
plug this into equation 2:-
5(-3y-13) + 7y = -9
-15y - 65 + 7y = -9
-8y = 56
y = -7
Now plug y = 7 into equation 1
x - 21 = -13
x = -13 + 21 = 8

solution is x = 8 , y = -7

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Let us draw a picture to make the things more clear.

Attached is the image.

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