SOLUTION: 2x^2+11x-6=0 How do you complete the square of this problem

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Question 373447: 2x^2+11x-6=0 How do you complete the square of this problem


Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
2x^2+11x-6=0 How do you complete the square of this problem
:
The coefficient of x^2 should be 1, divide thru by 2
x^2 + 11%2F2x - 3 = 0
:
x^2 + 11%2F2x + __ = 3
:
(1%2F2*11%2F2)^2 = 121%2F16 will complete the square, add to both sides
:
x^2 + 11%2F2x + 121%2F16 = 3 + 121%2F16
:
x^2 + 11%2F2x + 121%2F16 = 48%2F16 + 121%2F16
:
x^2 + 11%2F2x + 121%2F16 = 169%2F16
:
(x + 11%2F4)^2 = 169%2F16
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Find the square root of both sides
x + 11%2F4 = +/-sqrt%28169%2F16%29
:
x + 11%2F4 = +/-13%2F4%29
Two solutions
x = -11%2F4 + 13%2F4%29
x = 2%2F4 = 1%2F2
and
x = -11%2F4 - 13%2F4%29
x = -24%2F4 = -6
:
:
You can confirm this by checking these values for x in the original problem