Question 210452
I am not sure what they are doing in class, but you got it right.
{{{9x^2-18x=-3}}}
Divide each term by 9 to get x^2 term to have coefficient of 1:
{{{x^2-2x=-1/3}}}
Divide coefficient of x by 2 and square. add result to both sides:
{{{x^2-2x+1=2/3}}}
Represent left side as perfect square:
{{{(x-1)^2=2/3}}}
Take square root of each side:
x-1=+-sqrt(2/3)
Solve for x:
x=1+-sqrt(2/3)
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Good Luck,
tutor_paul@yahoo.com