Updated/Repost.
Given: 3x + 2y + 7 = 5x +3y +10
Prove: m = -2
(Hint: slope)
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Answer:
3x + 2y = -2
Reason: This is because 3x + 2y = 10 for the variable y. 3x-10= 2y.
Since
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3x + 7 = -2
Reason: This is because 3x+10= 2y
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