Answer: Choice B
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Explanation:
Here's a slightly more detailed breakdown of what's going on
3x + 2y = 15 ... start with the first equation
3x + 2( y ) = 15 .... the parenthesis don't change the expression
3x + 2( 3x+5) = 15 ... replace y with 3x+5; since y = 3x+5
From here, you solve for x like you would any other single variable equation. Once you know x, you can determine y through y = 3x+5.
