SOLUTION: xsquared-8x=33

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Question 305982: xsquared-8x=33
Found 2 solutions by JBarnum, texttutoring:
Answer by JBarnum(2146) 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 1x%5E2%2B-8x%2B-33+=+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%2A1%2A-33=196.

Discriminant d=196 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--8%2B-sqrt%28+196+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-8%29%2Bsqrt%28+196+%29%29%2F2%5C1+=+11
x%5B2%5D+=+%28-%28-8%29-sqrt%28+196+%29%29%2F2%5C1+=+-3

Quadratic expression 1x%5E2%2B-8x%2B-33 can be factored:
1x%5E2%2B-8x%2B-33+=+1%28x-11%29%2A%28x--3%29
Again, the answer is: 11, -3. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-8%2Ax%2B-33+%29

Answer by texttutoring(324) About Me  (Show Source):
You can put this solution on YOUR website!
x^2 - 8x = 33

First, set one side equal to zero by subtracting 33 from both sides:
x^2 -8x - 33 = 0

Now, factor. Look for two numbers that multiply to -33 but add up to -8. These numbers are -11 and 3.

x^2 -8x - 33 = 0
(x-11)(x+3)=0

So, either x=11 or x=-3.