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3 years ago

A(x+1)(x-1)+b(x-2)(x+1)+(x+1)^2=9x-x-10 What is a+b?

Mathematics

1 answer:

igor_vitrenko [27]3 years ago

4 0

a(x+1)(x-1)+b(x-2)(x+1)+(x+1)^2=9x^2-x-10

(x+1)(a(x-1)+b(x-2)+(x+1))=(x+1)(9x-10)

a(x-1)+b(x-2)+x+1=9x-10

Now this equation is much simpler!

(a+b)x-a-2b+x+1=9x-10

(a+b)x-a-2b=8x-11

(a+b-8)x-a-2b-11=0

a+b-8=(a+2b-11)/x

I can't solve it 3 variables and 1 equations means infinite answers so yea.

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