SOLUTION: -5(a-4)+4squared = 7a

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Question 314866: -5(a-4)+4squared = 7a
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Did you mean 4*a squared
-5%28a-4%29%2B4a%5E2+=+7a
or 4squared??
-5%28a-4%29%2B4%5E2+=+7a
-5a%2B20%2B16=7a
36=2a
highlight%28+a=18%29
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If you meant the first one,
-5%28a-4%29%2B4a%5E2+=+7a
-5a%2B20%2B4a%5E2+=+7a
4a%5E2-5a%2B20=7a
4a%5E2-12a%2B20=0
a%5E2-3a%2B5=0
Use the quadratic formula,
a+=+%28-%28-3%29+%2B-+sqrt%28+%28-3%29%5E2-4%2A1%2A5+%29%29%2F%282%2A1%29+
a+=+%283+%2B-+sqrt%28+9-20+%29%29%2F2+
a+=+%283+%2B-+sqrt%28+-11%29%29%2F2+
highlight%28+a+=+%283+%2B-+sqrt%2811%29i%29%2F2+%29