Question 371647
what is the answer to the following equation using the substitution: x=3y-1, x+2y=9
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The answer to them depends on the question asked.  That could be one of several questions.
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If you want to solve for x and y, you should say that, not "what is the answer to..."
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x=3y-1
x+2y=9
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x+2y = 9
Sub eqn 1 for x
(3y-1) + 2y = 9
5y - 1 = 9
5y = 10
y = 2
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x = 3y-1
x = 5