SOLUTION: what is the way to solve 3(x+21)=-4(x-21)

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Question 987534: what is the way to solve 3(x+21)=-4(x-21)
Found 2 solutions by Alan3354, josmiceli:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
what is the way to solve 3(x+21)=-4(x-21)
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Step 1, eliminate the parentheses by multiplying.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+3%2A%28+x+%2B+21+%29++=+-4%2A%28+x+-+21+%29+
Use distributive law which says:
+a%2A%28+b+%2B+c+%29+=+a%2Ab+%2B+a%2Ac+
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+3x+%2B+63+=+-4x+%2B+84+
Add +4x+ to both sides
+7x+%2B+63+=+84+
Subtract +63+ from both sides
+7x+=+21+
Divide both sides by +7+
+x+=+3+
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check solution:
+3%2A%28+3+%2B+21+%29++=+-4%2A%28+3+-+21+%29+
+3%2A24+=+-4%2A%28+-18+%29+
Divide both sides by +6+
+3%2A4+=+-4%2A%28+3+%29+
+12+=+12+
OK