SOLUTION: what two numbers when added equal x but when multiplied equal -12?

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Question 954853: what two numbers when added equal x but when multiplied equal -12?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Call the numbers +a+ and +b+
+a+%2B+b+=+x+
+a%2Ab+=+-12+
---------------
+b+=+x+-+a+
By substitution:
+a%2A%28+x+-+a+%29+=+-12+
+a%5E2+-+a%2Ax+-+12+=+0+
+%28+a+-+4+%29%2A%28+a+%2B+3+%29+=+0+
+a+=+4+
and
+a%2Ab+=+-12+
+b+=+-12%2Fa+
+b+=+-12%2F4+
+b+=+-3+
----------------
The numbers are 4 and -3
check:
+a+%2B+b+=+x+
+4+%2B+-3+=+x+
+x+=+1+
+a%2A%28+x+-+a+%29+=+-12+
+4%2A%28+1+-+4+%29+=+-12+
+4%2A%28-3%29+=+-12+
+-12+=+-12+
OK