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\left(x+1\right)\times 3-\left(x-5\right)x=10
Variable x cannot be equal to any of the values -1,5 since division by zero is not defined. Multiply both sides of the equation by \left(x-5\right)\left(x+1\right), the least common multiple of x-5,x+1,\left(x+1\right)\left(x-5\right).
3x+3-\left(x-5\right)x=10
Use the distributive property to multiply x+1 by 3.
3x+3-\left(x^{2}-5x\right)=10
Use the distributive property to multiply x-5 by x.
3x+3-x^{2}+5x=10
To find the opposite of x^{2}-5x, find the opposite of each term.
8x+3-x^{2}=10
Combine 3x and 5x to get 8x.
8x+3-x^{2}-10=0
Subtract 10 from both sides.
8x-7-x^{2}=0
Subtract 10 from 3 to get -7.
-x^{2}+8x-7=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-8±\sqrt{8^{2}-4\left(-1\right)\left(-7\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 8 for b, and -7 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-8±\sqrt{64-4\left(-1\right)\left(-7\right)}}{2\left(-1\right)}
Square 8.
x=\frac{-8±\sqrt{64+4\left(-7\right)}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-8±\sqrt{64-28}}{2\left(-1\right)}
Multiply 4 times -7.
x=\frac{-8±\sqrt{36}}{2\left(-1\right)}
Add 64 to -28.
x=\frac{-8±6}{2\left(-1\right)}
Take the square root of 36.
x=\frac{-8±6}{-2}
Multiply 2 times -1.
x=-\frac{2}{-2}
Now solve the equation x=\frac{-8±6}{-2} when ± is plus. Add -8 to 6.
x=1
Divide -2 by -2.
x=-\frac{14}{-2}
Now solve the equation x=\frac{-8±6}{-2} when ± is minus. Subtract 6 from -8.
x=7
Divide -14 by -2.
x=1 x=7
The equation is now solved.
\left(x+1\right)\times 3-\left(x-5\right)x=10
Variable x cannot be equal to any of the values -1,5 since division by zero is not defined. Multiply both sides of the equation by \left(x-5\right)\left(x+1\right), the least common multiple of x-5,x+1,\left(x+1\right)\left(x-5\right).
3x+3-\left(x-5\right)x=10
Use the distributive property to multiply x+1 by 3.
3x+3-\left(x^{2}-5x\right)=10
Use the distributive property to multiply x-5 by x.
3x+3-x^{2}+5x=10
To find the opposite of x^{2}-5x, find the opposite of each term.
8x+3-x^{2}=10
Combine 3x and 5x to get 8x.
8x-x^{2}=10-3
Subtract 3 from both sides.
8x-x^{2}=7
Subtract 3 from 10 to get 7.
-x^{2}+8x=7
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{-x^{2}+8x}{-1}=\frac{7}{-1}
Divide both sides by -1.
x^{2}+\frac{8}{-1}x=\frac{7}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}-8x=\frac{7}{-1}
Divide 8 by -1.
x^{2}-8x=-7
Divide 7 by -1.
x^{2}-8x+\left(-4\right)^{2}=-7+\left(-4\right)^{2}
Divide -8, the coefficient of the x term, by 2 to get -4. Then add the square of -4 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-8x+16=-7+16
Square -4.
x^{2}-8x+16=9
Add -7 to 16.
\left(x-4\right)^{2}=9
Factor x^{2}-8x+16. 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-4\right)^{2}}=\sqrt{9}
Take the square root of both sides of the equation.
x-4=3 x-4=-3
Simplify.
x=7 x=1
Add 4 to both sides of the equation.