Hey i am attempting to CTS 4x^{2}+24x-18=0

i divide by four to make the a coefficient zero but then get lost at the 18/4 and dont know what do with that.

Any help is appreciated

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- Apr 21st 2013, 11:32 AMgramgilbCompleting the Square
Hey i am attempting to CTS 4x

^{2}+24x-18=0

i divide by four to make the a coefficient zero but then get lost at the 18/4 and dont know what do with that.

Any help is appreciated - Apr 21st 2013, 11:36 AMdokrbbRe: Completing the Square
you are trying to what... CTS?

- Apr 21st 2013, 11:44 AMgramgilbRe: Completing the Square
Ya i know the answer from the answer sheet but everytime i try i get the wrong answer.

The answer is supposed to be x=1/2(-6 plus/minus 3 √6) bu this way seems like it was divided by two and the a coefficient was 2... - Apr 21st 2013, 11:52 AMPlatoRe: Completing the Square
- Apr 21st 2013, 01:52 PMgramgilbRe: Completing the Square
ya i got it ty

- Apr 21st 2013, 09:08 PMibduttRe: Completing the Square
Foe such questions adopt the folloing algorithm.

Step - 1: Make coefficient = 1. in this case : divide by 4: x^2 + 6x - 9/2 = 0

step - 2: transfer the constant term to the RHS: we will get x^2 + 6x = 9/2

Step 3: Add the square of half the coefficient of x on both the sides of the equation. in this case the coefficient of x = 6; Half the coefficient of x = 3 and square of this is 9. Thus we have: x^2 + 6x + 9= 9/2 + 9

That gives ( x + 3 )^2 = 27/2 - Apr 21st 2013, 11:32 PMagentmulderRe: Completing the Square
- Apr 22nd 2013, 01:40 AMProve ItRe: Completing the Square