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Question 91724: Need help with this one: Solve by completing the square. Thank you :)
x^2-1/2x-3/16=0
answer choices:
a. -1/4, 3/4
b. -1/4, 2/3
c. -3/4, 1/4
Found 2 solutions by ankor@dixie-net.com, scott8148:
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! Solve by completing the square.
:
x^2 - 1/2x - 3/16 = 0
:
x^2 - 1/2x + ____ = +3/16
:
Find the value to complete the square, divide the coefficient of x by 2 & square
it: 1/2 * 1/2 = 1/4; (1/4)^2 = 1/16. Add that to both sides, you have:
:
x^2 - 1/2x + 1/16 = 3/16 + 1/16
:
(x - 1/4)^2 = 4/16
:
x - 1/4 = +/-Sqrt(4/16); find the square root of both sids
:
x - 1/4 = +/- 2/4
:
x = + 1/4 +/-2/4
:
Two solutions:
x = +1/4 + 2/4
x = +3/4
and
x = +1/4 - 2/4
x = -1/4
:
did this help you understand "completing the square"
Answer by scott8148(6628)  (Show Source):
You can put this solution on YOUR website! completing the square - step-by-step ... for ax^2+bx+c=0
1) by dividing or multiplying, set the coefficient of the squared term equal to one ... x^2+(b/a)x+(c/a)=0
2) by adding or subtracting, set the constant term (c/a) equal to zero ... x^2+(b/a)x=-(c/a)
3) add the square of one half of the x coefficient to both sides ... x^2+(b/a)x+(b/(2a))^2=-(c/a)+(b/(2a))^2
4) take the square root of both sides ...  , realizing the root is positive AND negative
in this case, x-(1/4)=1/2 and x-(1/4)=-1/2 ... x=3/4 and -1/4 ... looks like (a) is it
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