SOLUTION: (c-1)^2= 43.8 is given to me. How do i solve for c?

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Question 36437: (c-1)^2= 43.8 is given to me. How do i solve for c?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
(c-1)^2= 43.8
c^2-2c+1=43.8
c^2-2c-42.8=0
a=1,b=-2,c=-42.8
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B-2x%2B-42.8+=+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=%28-2%29%5E2-4%2A1%2A-42.8=175.2.

Discriminant d=175.2 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--2%2B-sqrt%28+175.2+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-2%29%2Bsqrt%28+175.2+%29%29%2F2%5C1+=+7.61815684310972
x%5B2%5D+=+%28-%28-2%29-sqrt%28+175.2+%29%29%2F2%5C1+=+-5.61815684310972

Quadratic expression 1x%5E2%2B-2x%2B-42.8 can be factored:
1x%5E2%2B-2x%2B-42.8+=+1%28x-7.61815684310972%29%2A%28x--5.61815684310972%29
Again, the answer is: 7.61815684310972, -5.61815684310972. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-2%2Ax%2B-42.8+%29

Hope this helps.
Cheers,
stan H.