SOLUTION: If you subtracr a number from its square, the result is 12 Find all such numbers

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Question 184870: If you subtracr a number from its square, the result is 12 Find all such numbers

Found 2 solutions by ankor@dixie-net.com, Earlsdon:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
If you subtract a number from its square, the result is 12. Find all such numbers
:
x^2 - x = 12
;
x^2 - x - 12 = 0
factor
(x-4)(x+3) = 0
Two solutions
x = +4
and
x = -3
:
Check the 2nd solution
(-3)^2 - (-3) = 12
9 + 3 = 12

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Let the number be n, so...
n%5E2-n+=+12 Subtract 12 from both sides.
n%5E2-n-12+=+0 Factor this quadratic equation.
%28n%2B3%29%28n-4%29+=+0 Apply the zero product rule.
n%2B3+=+0 or n-4+=+0 therefore:
n+=+-3 or n+=+4
Check:
%28-3%29%5E2-%28-3%29+=+12
9%2B3+=+12
12+=+12 OK!
4%5E2-4+=+12
16-4+=+12
12+=+12 OK!