Solve for x
x=-7
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x^{2}-1+\left(x-2\right)\times 5=3
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by x-2.
x^{2}-1+5x-10=3
Use the distributive property to multiply x-2 by 5.
x^{2}-11+5x=3
Subtract 10 from -1 to get -11.
x^{2}-11+5x-3=0
Subtract 3 from both sides.
x^{2}-14+5x=0
Subtract 3 from -11 to get -14.
x^{2}+5x-14=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=5 ab=-14
To solve the equation, factor x^{2}+5x-14 using formula x^{2}+\left(a+b\right)x+ab=\left(x+a\right)\left(x+b\right). To find a and b, set up a system to be solved.
-1,14 -2,7
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -14.
-1+14=13 -2+7=5
Calculate the sum for each pair.
a=-2 b=7
The solution is the pair that gives sum 5.
\left(x-2\right)\left(x+7\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=2 x=-7
To find equation solutions, solve x-2=0 and x+7=0.
x=-7
Variable x cannot be equal to 2.
x^{2}-1+\left(x-2\right)\times 5=3
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by x-2.
x^{2}-1+5x-10=3
Use the distributive property to multiply x-2 by 5.
x^{2}-11+5x=3
Subtract 10 from -1 to get -11.
x^{2}-11+5x-3=0
Subtract 3 from both sides.
x^{2}-14+5x=0
Subtract 3 from -11 to get -14.
x^{2}+5x-14=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=5 ab=1\left(-14\right)=-14
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-14. To find a and b, set up a system to be solved.
-1,14 -2,7
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -14.
-1+14=13 -2+7=5
Calculate the sum for each pair.
a=-2 b=7
The solution is the pair that gives sum 5.
\left(x^{2}-2x\right)+\left(7x-14\right)
Rewrite x^{2}+5x-14 as \left(x^{2}-2x\right)+\left(7x-14\right).
x\left(x-2\right)+7\left(x-2\right)
Factor out x in the first and 7 in the second group.
\left(x-2\right)\left(x+7\right)
Factor out common term x-2 by using distributive property.
x=2 x=-7
To find equation solutions, solve x-2=0 and x+7=0.
x=-7
Variable x cannot be equal to 2.
x^{2}-1+\left(x-2\right)\times 5=3
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by x-2.
x^{2}-1+5x-10=3
Use the distributive property to multiply x-2 by 5.
x^{2}-11+5x=3
Subtract 10 from -1 to get -11.
x^{2}-11+5x-3=0
Subtract 3 from both sides.
x^{2}-14+5x=0
Subtract 3 from -11 to get -14.
x^{2}+5x-14=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{-5±\sqrt{5^{2}-4\left(-14\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 5 for b, and -14 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-5±\sqrt{25-4\left(-14\right)}}{2}
Square 5.
x=\frac{-5±\sqrt{25+56}}{2}
Multiply -4 times -14.
x=\frac{-5±\sqrt{81}}{2}
Add 25 to 56.
x=\frac{-5±9}{2}
Take the square root of 81.
x=\frac{4}{2}
Now solve the equation x=\frac{-5±9}{2} when ± is plus. Add -5 to 9.
x=2
Divide 4 by 2.
x=-\frac{14}{2}
Now solve the equation x=\frac{-5±9}{2} when ± is minus. Subtract 9 from -5.
x=-7
Divide -14 by 2.
x=2 x=-7
The equation is now solved.
x=-7
Variable x cannot be equal to 2.
x^{2}-1+\left(x-2\right)\times 5=3
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by x-2.
x^{2}-1+5x-10=3
Use the distributive property to multiply x-2 by 5.
x^{2}-11+5x=3
Subtract 10 from -1 to get -11.
x^{2}+5x=3+11
Add 11 to both sides.
x^{2}+5x=14
Add 3 and 11 to get 14.
x^{2}+5x+\left(\frac{5}{2}\right)^{2}=14+\left(\frac{5}{2}\right)^{2}
Divide 5, the coefficient of the x term, by 2 to get \frac{5}{2}. Then add the square of \frac{5}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+5x+\frac{25}{4}=14+\frac{25}{4}
Square \frac{5}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}+5x+\frac{25}{4}=\frac{81}{4}
Add 14 to \frac{25}{4}.
\left(x+\frac{5}{2}\right)^{2}=\frac{81}{4}
Factor x^{2}+5x+\frac{25}{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{5}{2}\right)^{2}}=\sqrt{\frac{81}{4}}
Take the square root of both sides of the equation.
x+\frac{5}{2}=\frac{9}{2} x+\frac{5}{2}=-\frac{9}{2}
Simplify.
x=2 x=-7
Subtract \frac{5}{2} from both sides of the equation.
x=-7
Variable x cannot be equal to 2.
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