SOLUTION: Find the value of x. 4x^2-36x=-56

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Question 638646: Find the value of x.
4x^2-36x=-56
Found 2 solutions by reviewermath, lwsshak3:
Answer by reviewermath(1029) 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-36x%2B56+=+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=%28-36%29%5E2-4%2A4%2A56=400.

Discriminant d=400 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--36%2B-sqrt%28+400+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-36%29%2Bsqrt%28+400+%29%29%2F2%5C4+=+7
x%5B2%5D+=+%28-%28-36%29-sqrt%28+400+%29%29%2F2%5C4+=+2

Quadratic expression 4x%5E2%2B-36x%2B56 can be factored:
4x%5E2%2B-36x%2B56+=+4%28x-7%29%2A%28x-2%29
Again, the answer is: 7, 2. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+4%2Ax%5E2%2B-36%2Ax%2B56+%29

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Find the value of x.
4x^2-36x=-56
4x^2-36x+56=0
divide by 4
x^2-9x+14=0
factor
(x-7)(x-2)=0
x=7
or
x=2