Help with substitution! (With pictures-2 separate questions) thanks!
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Answer:
Explanation contains answer.
Step-by-step explanation:
Question 1:
I would perfer to solve the first equation for y because there is only one operation to perform on both sides and it is subtraction of 2x on both sides.
The other equation requires two steps to isolate y; subtracting 3x on both sides then multiplying both sides by -1.
So basically solving the first one for y because it has coefficient 1.
Question 2:
They solved the 2nd equation for y and plugged into itself instead of plugging it into 1st equation.