Question

Solve using the substitution method. x + 2y = 9 x + 3y = 13

Answer 1

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