SOLUTION: If x=3 and x=5, then form a quadratic equation

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Question 113333: If x=3 and x=5, then form a quadratic equation
Found 2 solutions by checkley71, Fombitz:
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
X^2-8X+15=0 ANSWER.
(X-3)(X-5)=0
X-3=0
X=3
X-5=0
X=5

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
From x=3 and x=5 you can form a quadratic equation that says
%28x-3%29%28x-5%29=0
Since x=3 and x=5 are both solutions,
%28x-3%29%28x-5%29=0
%283-3%29%283-5%29=0
0%28-2%29=0
0=0
True.
%28x-3%29%28x-5%29=0
%285-3%29%285-5%29=0
2%280%29=0
0=0
True.
Now to expand the equation you use the FOIL method (First, Outer, Inner, Last)
%28x-3%29%28x-5%29=%28x%2B%28-3%29%29%28x%2B%28-5%29%29
First : %28highlight%28x%29%2B%28-3%29%29%28highlight%28x%29%2B%28-5%29%29=%28x%29%28x%29=x%5E2
Outer : %28highlight%28x%29%2B%28-3%29%29%28x%2Bhighlight%28-5%29%29=%28x%29%28-5%29=-5x
Inner : %28x%2Bhighlight%28-3%29%29%28highlight%28x%29%2B%28-5%29%29=%28-3%29%28x%29=-3x
Last : %28x%2Bhighlight%28-3%29%29%28x%2Bhighlight%28-5%29%29=%28-3%29%28-5%29=15
Then you sum all of the terms
%28x-3%29%28x-5%29=x%5E2%2B%28-5x%29%2B%28-3x%29%2B15
%28x-3%29%28x-5%29=x%5E2-8x%2B15=0
Therefore your quadratic equation with roots x=3 and x=5 is
f%28x%29=x%5E2-8x%2B15