SOLUTION: what is the answer to y=2x^2+8x+5 in the form : a(x-h)^2 + k

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Question 914911: what is the answer to y=2x^2+8x+5 in the form : a(x-h)^2 + k
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+y+=+2x%5E2+%2B+8x+%2B+5+
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+y+=+a%2A%28+x-h+%29%5E2+%2B+k+
+y+=+a%2A%28+x%5E2+-+2h%2Ax+%2B+h%5E2+%29+%2B+k+
+y+=+a%2Ax%5E2+-+2a%2Ah%2Ax+%2B+a%2Ah%5E2+%2B+k+
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From this, I get:
(1) +a+=+2+
(2) +-2a%2Ah+=+8+
(3) +a%2Ah%5E2+%2B+k+=+5+
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Substitute (1) into (2)
(2) +-2%2A2%2Ah+=+8+
(2) +h+=+-2+
and
(3) +2%2A%28-2%29%5E2+%2B+k+=+5+
(3) +8+%2B+k+=+5+
(3) +k+=+-3+
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So, the answer is:
+y+=+2%2A%28+x-%28-2%29+%29%5E2+-+3+
+y+=+2%2A%28+x%2B2+%29%5E2+-+3+
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Check answer:
+y+=+2%2A%28+x%5E2+%2B+4x+%2B+4+%29+-+3+
+y+=+2x%5E2+%2B+8x+%2B+8+-+3+
+y+=+2x%5E2+%2B+8x+%2B+5+
OK