How do you solve the system of equations #7x - 9y = 29# and #7x + 2y = - 15#?

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Answer 1 · 2017-03-17T01:01:03

x = -1
y= -4

(-1, -4)

#7x - 9y = 29#
#7x + 2y = -15#

Subtract the like terms and, since the 7x's cancel out,
you're left with

-11y = 44

Divide both sides by -11 to get:

#y = -4#

Plug this value into one of the equations to get x, like this:

#7x + 2y = -15#
#7x + 2(-4) = -15#
#7x - 8 = -15 #7x = -7#

#x = -1#