SOLUTION: w^2-18w+81 =0

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Question 26435: w^2-18w+81 =0
Answer by Alwayscheerful(414) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation aw%5E2%2Bbw%2Bc=0 (in our case 1w%5E2%2B-18w%2B81+=+0) has the following solutons:

w%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=%28-18%29%5E2-4%2A1%2A81=0.

Discriminant d=0 is zero! That means that there is only one solution: w+=+%28-%28-18%29%29%2F2%5C1.
Expression can be factored: 1w%5E2%2B-18w%2B81+=+1%28w-9%29%2A%28w-9%29

Again, the answer is: 9, 9. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-18%2Ax%2B81+%29

Hope this helps!