x + 2y = 9
x + 3y = 13
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Solve for x in the first equation. Subtract 2y from both sides.
x = 9 - 2y
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Plug x into the second equation.
(9 - 2y) + 3y = 13
Combine like terms.
9 + y = 13
Subtract 9 from both sides.
y = 4
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Plug y back into the first equation.
x + 2(4) = 9
x + 8 = 9
Subtract 8 from both sides.
x = 1
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x = 1
y = 4