SOLUTION: f(x) = x^2 + 4x - 12 Solve by completing the square.

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Question 1025366: f(x) = x^2 + 4x - 12 Solve by completing the square.
Found 2 solutions by josgarithmetic, ankor@dixie-net.com:
Answer by josgarithmetic(39617) About Me  (Show Source):
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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f(x) = x^2 + 4x - 12 Solve by completing the square.
:
x^2 + 4x + __ = 12
Complete the square, divide the coefficient of x by 2 and square it (4/2)^2
add to both sides
x^2 + 4x + 4 = 12 + 4
x^2 + 4x + 4 = 16
A perfect square which is:
(x+2)^2 = 16
Find the square root of both side
x + 2 = +/-sqrt%2816%29
x + 2 = +/- 4
Subtract 2 from both sides, two solutions
x = -2 + 4
x = 2
and
x = -2 - 4
x = -6