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x=-1
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\left(4-\frac{2\left(-x+1\right)}{-x+4}\right)\left(-x+4\right)=16
Express 2\times \frac{-x+1}{-x+4} as a single fraction.
\left(4-\frac{2\left(-x\right)+2}{-x+4}\right)\left(-x+4\right)=16
Use the distributive property to multiply 2 by -x+1.
\left(\frac{4\left(-x+4\right)}{-x+4}-\frac{2\left(-x\right)+2}{-x+4}\right)\left(-x+4\right)=16
To add or subtract expressions, expand them to make their denominators the same. Multiply 4 times \frac{-x+4}{-x+4}.
\frac{4\left(-x+4\right)-\left(2\left(-x\right)+2\right)}{-x+4}\left(-x+4\right)=16
Since \frac{4\left(-x+4\right)}{-x+4} and \frac{2\left(-x\right)+2}{-x+4} have the same denominator, subtract them by subtracting their numerators.
\frac{-4x+16+2x-2}{-x+4}\left(-x+4\right)=16
Do the multiplications in 4\left(-x+4\right)-\left(2\left(-x\right)+2\right).
\frac{-2x+14}{-x+4}\left(-x+4\right)=16
Combine like terms in -4x+16+2x-2.
\frac{\left(-2x+14\right)\left(-x+4\right)}{-x+4}=16
Express \frac{-2x+14}{-x+4}\left(-x+4\right) as a single fraction.
\frac{-2x\left(-x\right)-8x+14\left(-x\right)+56}{-x+4}=16
Use the distributive property to multiply -2x+14 by -x+4.
\frac{2xx-8x+14\left(-x\right)+56}{-x+4}=16
Multiply -2 and -1 to get 2.
\frac{2x^{2}-8x+14\left(-x\right)+56}{-x+4}=16
Multiply x and x to get x^{2}.
\frac{2x^{2}-8x+14\left(-x\right)+56}{-x+4}-16=0
Subtract 16 from both sides.
\frac{2x^{2}-8x+14\left(-x\right)+56}{-x+4}-\frac{16\left(-x+4\right)}{-x+4}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply 16 times \frac{-x+4}{-x+4}.
\frac{2x^{2}-8x+14\left(-x\right)+56-16\left(-x+4\right)}{-x+4}=0
Since \frac{2x^{2}-8x+14\left(-x\right)+56}{-x+4} and \frac{16\left(-x+4\right)}{-x+4} have the same denominator, subtract them by subtracting their numerators.
\frac{2x^{2}-8x-14x+56+16x-64}{-x+4}=0
Do the multiplications in 2x^{2}-8x+14\left(-x\right)+56-16\left(-x+4\right).
\frac{2x^{2}-6x-8}{-x+4}=0
Combine like terms in 2x^{2}-8x-14x+56+16x-64.
2x^{2}-6x-8=0
Variable x cannot be equal to 4 since division by zero is not defined. Multiply both sides of the equation by -x+4.
x=\frac{-\left(-6\right)±\sqrt{\left(-6\right)^{2}-4\times 2\left(-8\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -6 for b, and -8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-6\right)±\sqrt{36-4\times 2\left(-8\right)}}{2\times 2}
Square -6.
x=\frac{-\left(-6\right)±\sqrt{36-8\left(-8\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-6\right)±\sqrt{36+64}}{2\times 2}
Multiply -8 times -8.
x=\frac{-\left(-6\right)±\sqrt{100}}{2\times 2}
Add 36 to 64.
x=\frac{-\left(-6\right)±10}{2\times 2}
Take the square root of 100.
x=\frac{6±10}{2\times 2}
The opposite of -6 is 6.
x=\frac{6±10}{4}
Multiply 2 times 2.
x=\frac{16}{4}
Now solve the equation x=\frac{6±10}{4} when ± is plus. Add 6 to 10.
x=4
Divide 16 by 4.
x=-\frac{4}{4}
Now solve the equation x=\frac{6±10}{4} when ± is minus. Subtract 10 from 6.
x=-1
Divide -4 by 4.
x=4 x=-1
The equation is now solved.
x=-1
Variable x cannot be equal to 4.
\left(4-\frac{2\left(-x+1\right)}{-x+4}\right)\left(-x+4\right)=16
Express 2\times \frac{-x+1}{-x+4} as a single fraction.
\left(4-\frac{2\left(-x\right)+2}{-x+4}\right)\left(-x+4\right)=16
Use the distributive property to multiply 2 by -x+1.
\left(\frac{4\left(-x+4\right)}{-x+4}-\frac{2\left(-x\right)+2}{-x+4}\right)\left(-x+4\right)=16
To add or subtract expressions, expand them to make their denominators the same. Multiply 4 times \frac{-x+4}{-x+4}.
\frac{4\left(-x+4\right)-\left(2\left(-x\right)+2\right)}{-x+4}\left(-x+4\right)=16
Since \frac{4\left(-x+4\right)}{-x+4} and \frac{2\left(-x\right)+2}{-x+4} have the same denominator, subtract them by subtracting their numerators.
\frac{-4x+16+2x-2}{-x+4}\left(-x+4\right)=16
Do the multiplications in 4\left(-x+4\right)-\left(2\left(-x\right)+2\right).
\frac{-2x+14}{-x+4}\left(-x+4\right)=16
Combine like terms in -4x+16+2x-2.
\frac{\left(-2x+14\right)\left(-x+4\right)}{-x+4}=16
Express \frac{-2x+14}{-x+4}\left(-x+4\right) as a single fraction.
\frac{-2x\left(-x\right)-8x+14\left(-x\right)+56}{-x+4}=16
Use the distributive property to multiply -2x+14 by -x+4.
\frac{2xx-8x+14\left(-x\right)+56}{-x+4}=16
Multiply -2 and -1 to get 2.
\frac{2x^{2}-8x+14\left(-x\right)+56}{-x+4}=16
Multiply x and x to get x^{2}.
2x^{2}-8x+14\left(-1\right)x+56=16\left(-x+4\right)
Variable x cannot be equal to 4 since division by zero is not defined. Multiply both sides of the equation by -x+4.
2x^{2}-8x-14x+56=16\left(-x+4\right)
Multiply 14 and -1 to get -14.
2x^{2}-22x+56=16\left(-x+4\right)
Combine -8x and -14x to get -22x.
2x^{2}-22x+56=-16x+64
Use the distributive property to multiply 16 by -x+4.
2x^{2}-22x+56+16x=64
Add 16x to both sides.
2x^{2}-6x+56=64
Combine -22x and 16x to get -6x.
2x^{2}-6x=64-56
Subtract 56 from both sides.
2x^{2}-6x=8
Subtract 56 from 64 to get 8.
\frac{2x^{2}-6x}{2}=\frac{8}{2}
Divide both sides by 2.
x^{2}+\left(-\frac{6}{2}\right)x=\frac{8}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-3x=\frac{8}{2}
Divide -6 by 2.
x^{2}-3x=4
Divide 8 by 2.
x^{2}-3x+\left(-\frac{3}{2}\right)^{2}=4+\left(-\frac{3}{2}\right)^{2}
Divide -3, the coefficient of the x term, by 2 to get -\frac{3}{2}. Then add the square of -\frac{3}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-3x+\frac{9}{4}=4+\frac{9}{4}
Square -\frac{3}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-3x+\frac{9}{4}=\frac{25}{4}
Add 4 to \frac{9}{4}.
\left(x-\frac{3}{2}\right)^{2}=\frac{25}{4}
Factor x^{2}-3x+\frac{9}{4}. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x-\frac{3}{2}\right)^{2}}=\sqrt{\frac{25}{4}}
Take the square root of both sides of the equation.
x-\frac{3}{2}=\frac{5}{2} x-\frac{3}{2}=-\frac{5}{2}
Simplify.
x=4 x=-1
Add \frac{3}{2} to both sides of the equation.
x=-1
Variable x cannot be equal to 4.
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