SOLUTION: Solve the problem. For g(x)=2x(squared)-5x, find all values of a for which g(a)=7

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Question 427455: Solve the problem.

For g(x)=2x(squared)-5x, find all values of a for which g(a)=7

Found 2 solutions by jorel1380, nerdybill:
Answer by jorel1380(3719) About Me  (Show Source):
You can put this solution on YOUR website!
If g(x)=2x^2-5x, then for 7 we get:
7=2x^2-5x
0 = 2x^2-5x-7
0 = (2x-7)(x+1)
Therefore, x= either 7/2 or -1
Checking, we get
7=2(-1)^2-5(-1)
7=2*1+5
7=7
and
7=2(7/2)^2-5(7/2)
7=2(49/4)-35/2
8=49-35/2
7=14/2
7=7.

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
For g(x)=2x(squared)-5x, find all values of a for which g(a)=7
.
g%28x%29+=+2x%5E2+-+5x
set g(x) to 7 and solve for x:
7+=+2x%5E2+-+5x
0+=+2x%5E2+-+5x+-+7
0+=+%282x-7%29%28x%2B1%29
x = {-1, 7/2}
.
So,
a can be -1 or 7/2