SOLUTION: x2 − x = 12

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Question 1205825: x2 − x = 12
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39613) About Me  (Show Source):
You can put this solution on YOUR website!
say exactly what help you need.

Factoring? Try this:
x%5E2-x%29=12
x%28x-1%29=12, two factors which differ by 1, and product is 12;
x%28x-1%29=12=4%2A3

highlight%28x=4%29

Answer by ikleyn(52754) About Me  (Show Source):
You can put this solution on YOUR website!
.

This equation is nice to solve it by factoring.


Watch my steps attentively.


Write your equation in standard form of quadratic equation

    x^2 - x - 12 = 0.


Factor left side mentally in your head

    (x-4)*(x+3)= 0.


From here, you see that there are two roots, 4 and -3.


ANSWER.  The given equation has two roots, 4 and -3.

Solved in full, with all necessary explanations.


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