SOLUTION: 4x^2-8x+2=0 need help with quadratic formula

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Question 459133: 4x^2-8x+2=0 need help with quadratic formula
Answer by rwm(914) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 4x%5E2%2B-8x%2B2+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%28-8%29%5E2-4%2A4%2A2=32.

Discriminant d=32 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--8%2B-sqrt%28+32+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-8%29%2Bsqrt%28+32+%29%29%2F2%5C4+=+1.70710678118655
x%5B2%5D+=+%28-%28-8%29-sqrt%28+32+%29%29%2F2%5C4+=+0.292893218813452

Quadratic expression 4x%5E2%2B-8x%2B2 can be factored:
4x%5E2%2B-8x%2B2+=+4%28x-1.70710678118655%29%2A%28x-0.292893218813452%29
Again, the answer is: 1.70710678118655, 0.292893218813452. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+4%2Ax%5E2%2B-8%2Ax%2B2+%29