SOLUTION: Find a positive value of C so that the following trinomial is factorable. x^2-7x+c

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Question 687074: Find a positive value of C so that the following trinomial is factorable.
x^2-7x+c
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
Find a positive value of C so that the following trinomial is factorable.
x^2-7x+c
In order to be able to factor this...we need to split the -7 into two numbers that will add back together and get -7. Because c has to be positive, and we need to be able to multiply those same two numbers back together to get it, both numbers have to be negative. There are several possibilities:
(-1)(-6)=highlight%286%29
(-2)(-5)=highlight%2810%29
(-3)(-4)=highlight%2812%29
Any of them will work:
x%5E2-7x%2B6=%28x-1%29%28x-6%29
x%5E2-7x%2B10=%28x-2%29%28x-5%29
x%5E2-7x%2B12=%28x-3%29%28x-4%29
I hope that cleared things up.