-2y-39=5y-18
Add 2y to both sides and combine terms.
-2y+2y-39 = 5y+2y-18
-39=7y-18
Add 18 to both sides and combine terms.
-39+18 = 7y-18+18
-21 = 7y
Divide both sides by 7
-21/7 = 7y/7
-3 = y
Your other posts are done using the same process.
-2y-39=5y-18
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