posted by lisa on .
it is called completing the square
here is the equation 4x^2-4x+1=9 if anyone can help me please do okay i really need ot understand this
Move the numbers to the other side.
4x^2 -4x = 9-1
4x^2 -4x = 8
Now factor out 4 to make things easier.
x^2 -x =2 but remember we have all of that multiplied by 4.
The completed square goes where I place the Y.
x^2 - x +Y = 2 and to keep everything equal we must add Y to the right side, also.
x^2 - x + Y = 2 + Y
To determine what number completes the square, take 1/2 the x term and square it. 1/2 of 1 is 1/2 and 1/2 squared is 1/4. Now add 1/4 to both sides like this.
x^2 - x + 1/4 = 2 + 1/4 = 2.25
Now factor the left side. It is a perfect square now so it will be
(x - 1/2)^2 = 2.25
Now take the square root of both sides and solve for x. I hope this helps.
solving polynomial long division