SOLUTION: what is the answer to a^2+16a+15?

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Question 582164: what is the answer to a^2+16a+15?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+a%5E2+%2B+16a+%2B+15+=+%28+a+%2B+15+%29%2A%28+a+%2B+1+%29+
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You can find this by completing the square
+a%5E2+%2B+16a+%2B+%2816%2F2%29%5E2+=+-15+%2B+%2816%2F2%29%5E2+
+a%5E2+%2B+16a+%2B+64+=+-15+%2B+64+
+%28+a+%2B+8+%29%5E2+=+49+
+%28+a+%2B+8+%29%5E2+=+7%5E2+
+a+%2B+8+=+7+
+a+=+-1+
and, also,
+a+%2B+8+=+-7+
+a+=+-15+
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rewrite these as:
+a+%2B+1+=+0+
+a+%2B+15+=+0+
and
+%28+a+%2B+1+%29%2A%28+a+%2B+15+%29+=+0+
+%28+a+%2B+1+%29%2A%28+a+%2B+15+%29+=+a%5E2+%2B+16a+%2B+15+