SOLUTION: how doo i Solve the equation by graphing x2 - 5x - 24 = 0

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Question 306779: how doo i Solve the equation by graphing x2 - 5x - 24 = 0
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
You can factor to find the zeros.
x%5E2+-+5x+-+24+=+0
%28x-8%29%28x%2B3%29=0
Zeros at x=-3 and x=8.
The vertex is then at x=%288-3%29%2F2=5%2F2.
We can switch to vertex mode by completing the square.
%28x%5E2-5x%2B25%2F4%29-24-25%2F4=0
%28x-5%2F2%29%5E2-96%2F4-25%2F4=0
%28x-5%2F2%29%5E2-121%2F4=0
So the vertex is (5/2,-121/4).
Now you can hand sketch the parabola with all of these points.