SOLUTION: what adds up to 2 but multiplies to -1

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Question 858975: what adds up to 2 but multiplies to -1
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.A%2BB=2
2.A%2AB=-1
From eq. 2,
A=-1%2FB
Substitute into eq. 1,
-1%2FB%2BB=2
-1%2BB%5E2=2B
B%5E2-2B=1
B%5E2-2B%2B1=1%2B1
%28B-1%29%5E2=2
B-1=0+%2B-+sqrt%282%29
B=1+%2B-+sqrt%282%29
From eq. 1,
A=2-B
A=2-%281%2B-+sqrt%282%29%29
A=1+%2B-+sqrt%282%29 (in this case it should be -/+ but there's no symbol for that)
So then,
A=1-sqrt%282%29 and B=1%2Bsqrt%282%29
or
A=1%2Bsqrt%282%29 and B%2B1-sqrt%282%29