Solve for x
x=-\frac{1}{12}\approx -0.083333333
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3\left(2x+1\right)^{2}-5\left(x-1\right)^{2}=7x^{2}-14x-5
Multiply both sides of the equation by 15, the least common multiple of 5,3,15.
3\left(4x^{2}+4x+1\right)-5\left(x-1\right)^{2}=7x^{2}-14x-5
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(2x+1\right)^{2}.
12x^{2}+12x+3-5\left(x-1\right)^{2}=7x^{2}-14x-5
Use the distributive property to multiply 3 by 4x^{2}+4x+1.
12x^{2}+12x+3-5\left(x^{2}-2x+1\right)=7x^{2}-14x-5
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-1\right)^{2}.
12x^{2}+12x+3-5x^{2}+10x-5=7x^{2}-14x-5
Use the distributive property to multiply -5 by x^{2}-2x+1.
7x^{2}+12x+3+10x-5=7x^{2}-14x-5
Combine 12x^{2} and -5x^{2} to get 7x^{2}.
7x^{2}+22x+3-5=7x^{2}-14x-5
Combine 12x and 10x to get 22x.
7x^{2}+22x-2=7x^{2}-14x-5
Subtract 5 from 3 to get -2.
7x^{2}+22x-2-7x^{2}=-14x-5
Subtract 7x^{2} from both sides.
22x-2=-14x-5
Combine 7x^{2} and -7x^{2} to get 0.
22x-2+14x=-5
Add 14x to both sides.
36x-2=-5
Combine 22x and 14x to get 36x.
36x=-5+2
Add 2 to both sides.
36x=-3
Add -5 and 2 to get -3.
x=\frac{-3}{36}
Divide both sides by 36.
x=-\frac{1}{12}
Reduce the fraction \frac{-3}{36} to lowest terms by extracting and canceling out 3.
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