SOLUTION: solve 2x^2+8x-16

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Question 55474: solve
2x^2+8x-16
Answer by tutorcecilia(2152) About Me  (Show Source):
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2x^2+8x-16 [Use the quadratic formula to solve]
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
Let a=2; b=8 and c=-16
.
x+=+%28-8+%2B-+sqrt%28+8%5E2-%284%29%282%29%28-16%29+%29%29%2F%28%282%29%282%29%29+
.
x+=+%28%28-8+%2B-+sqrt%28+64-%28-128%29%29+%29%29%2F%28%284%29%29%29+
.
x+=+%28%28%28-8+%2B-+sqrt%28+192%29%29+%29%29%2F%28%284%29%29%29%29+
.
x+=+%28%28%28-8+%2B+sqrt%28+192%29%29+%29%29%2F%28%284%29%29%29+%29 = 1.464
.
x+=+%28%28%28-8+-+sqrt%28+192%29%29+%29%29%2F%28%284%29%29%29%29+.=-5.464
.
So, x = 1.464 or x=-5.464
check by plugging each value back into the original equation and solving.