y = x + 6
y = -7x - 10
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Solve for x in the first equation. Subtract y and x from both sides.
-x = 6 - y
Divide both sides by -1.
x = -6 + y
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Plug x into the second equation.
y = -7(-6 + y) - 10
Distribute -7 inside the parentheses.
y = 42 - 7y - 10
Combine like terms.
y = 32 - 7y
Add 7y to both sides.
8y = 32
Divide both sides by 8.
y = 4
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Plug 4 for y into the first equation.
4 = x + 6
Subtract 6 from both sides.
x = -2
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Your answer is -2; x = -2 satisfies both equations.