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Question 725557: Okay, been messing with the problem for quite some time. Please help with set up, I seem to be missing something key to the problem:
How old is Blanche today if the square of her age 3 years from now, minus 10 times her age 2 years ago is 50. I keep thinking it must be something like :
(x+3)^2 - 10x-2=50
But it is not working out.
Answer by jim_thompson5910(35256)   (Show Source):
You can put this solution on YOUR website! the square of her age 3 years from now ---> (x+3)^2
10 times her age 2 years ago ----> 10(x-2)
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"How old is Blanche today if the square of her age 3 years from now, minus 10 times her age 2 years ago is 50"
turns into
(x+3)^2 - 10(x - 2) = 50
Solve for x
(x+3)^2 - 10(x - 2) = 50
x^2 + 6x + 9 - 10(x - 2) = 50
x^2 + 6x + 9 - 10x + 20 = 50
x^2 + 6x + 9 - 10x + 20 - 50 = 0
x^2-4x-21 = 0
(x-7)(x+3) = 0
x-7 = 0 or x+3 = 0
x = 7 or x = -3
Ignore the negative answer.
So the only solution is x = 7
This means that Blanche is 7 years old currently.
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