SOLUTION: Solve cx^2-ax=b by completing the square.

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Question 983829: Solve cx^2-ax=b by completing the square.
Answer by Timnewman(323) About Me  (Show Source):
You can put this solution on YOUR website!
Hi dear!
To solve x%5E%282%29%2B2.5x=1.6 using completing the square method,take half of 2.5(i.e%281%2F2%29%282.5%29) square it,and add the result to both sides of the equation.
Here is the working;
x%5E%282%29%2B2.5x=1.6
x%5E2%2B2.5x%2B%282.5%2F2%29%5E%282%29=1.6%2B%282.5%2F2%29%5E%282%29
%28x%2B%282.5%2F2%29%29%5E%282%29=1.6%2B%286.25%2F4
%28x%2B%282.5%2F2%29%29%5E%282%29=6.4%2B6.25
x%2B%282.5%2F2%29=sqrt%2812.65%29
x=%2B-3.6-%282.5%2F2%29
x= 3.6-1.25 or -3.6-1.25
x=2.35 or -4.85