Question 220847: Dear Tutor,
Please help me solve this tedious math problem. Your help is GREATLY appreciated. Thanks so much!!! :)
Help me solve this by completing the square by the way please.
9x^2-12x=14
Answer by likaaka(51)   (Show Source):
You can put this solution on YOUR website!
9x^2-12x=14, divide thru by the coefficient of the squared term in this case a 9 (basically you need the coefficient of the squared term to be 1)
(9x^2)/(9) + (-12x)/(9) = 14/9, simplify the equation
x^2-(4/3)x=14/9, take 1/2 the coefficient of the x-term and square it & be sure to take the sign
1/2 of -4/3 is -2/3 (this number, -2/3, will be used later)and (-2/3)^2 is 4/9, now add this number to both sides of the equation
x^2-4x +(4/9)=8 +(4/9), convert the left-hand side to squared form and simplify the right hand side (this is where you use the sign that you took note of earlier and insert it into the middle of the parenthetical part
(x-(2/3))^2=76/9
Now you must solve for x, start by taking the square root of both sides
x-(2/3)= + or - the square root of (76/9)
the square root of (76/9) simplifies to 2 root 19 or 2 times the square root of 19 all over 3
now add (2/3) to both sides
x= + or - (2 root 14)/3 + (2/3)
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