Answer: Choice B)
2x+5(2x+3) = 3
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Reasoning:
We start with the second equation 2x+5y = 3
Since y = 2x+3 from the first equation, we can replace every copy of y with (2x+3). This replacement is valid because y and 2x+3 are the same.
So that's how we go from 2x+5y = 3 to 2x+5(2x+3) = 3
This replacement is done to get rid of the y variable, and it allows us to solve for x later on.
