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

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Answer 1 · 2017-03-17T01:01:03

x = -1
y= -4

(-1, -4)

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

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

-11y = 44

Divide both sides by -11 to get:

$y = - 4$ $y = -4$

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

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

$x = - 1$ $x = -1$

How do you solve the system of equations 7x−9y=297x - 9y = 29 and 7x+2y=−157x + 2y = - 15?