SOLUTION: Solve the equation. a^2-a-2=0

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Question 80544: Solve the equation.
a^2-a-2=0
Answer by tutorcecilia(2152) About Me  (Show Source):
You can put this solution on YOUR website!
%28a%5E2-a-2%29=0 [solve for the a-term by factoring the polynomial]
(a+1)(a-2)=0 [set each factor equal to zero and solve]
a+1=0
a=-1
and
a-2=0
a=2
.
So, the answers are x = -1 and x=2
.
check by plugging the values for x back into the original equation and solve.
%28a%5E2-a-2%29=0
Let x=-1
%28%28-1%29%5E2-%28-1%29-2%29=0
1+1-2=0
2-2=0
0=0 [checks out]
and
%28a%5E2-a-2%29=0
Let x=2
%28%282%29%5E2-%282%29-2%29=0
4-2-2=0
4-4-0
0=0 [also checks out]
%28a%5E2-a-2%29=0