Solve for x
x=-5
x=4
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\left(x-2\right)\times 5+\left(x-2\right)^{2}-14=0
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)^{2}, the least common multiple of x-2,x^{2}-4x+4.
5x-10+\left(x-2\right)^{2}-14=0
Use the distributive property to multiply x-2 by 5.
5x-10+x^{2}-4x+4-14=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x-10+x^{2}+4-14=0
Combine 5x and -4x to get x.
x-6+x^{2}-14=0
Add -10 and 4 to get -6.
x-20+x^{2}=0
Subtract 14 from -6 to get -20.
x^{2}+x-20=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=1 ab=-20
To solve the equation, factor x^{2}+x-20 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.
-1,20 -2,10 -4,5
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 -20.
-1+20=19 -2+10=8 -4+5=1
Calculate the sum for each pair.
a=-4 b=5
The solution is the pair that gives sum 1.
\left(x-4\right)\left(x+5\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=4 x=-5
To find equation solutions, solve x-4=0 and x+5=0.
\left(x-2\right)\times 5+\left(x-2\right)^{2}-14=0
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)^{2}, the least common multiple of x-2,x^{2}-4x+4.
5x-10+\left(x-2\right)^{2}-14=0
Use the distributive property to multiply x-2 by 5.
5x-10+x^{2}-4x+4-14=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x-10+x^{2}+4-14=0
Combine 5x and -4x to get x.
x-6+x^{2}-14=0
Add -10 and 4 to get -6.
x-20+x^{2}=0
Subtract 14 from -6 to get -20.
x^{2}+x-20=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=1 ab=1\left(-20\right)=-20
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-20. To find a and b, set up a system to be solved.
-1,20 -2,10 -4,5
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 -20.
-1+20=19 -2+10=8 -4+5=1
Calculate the sum for each pair.
a=-4 b=5
The solution is the pair that gives sum 1.
\left(x^{2}-4x\right)+\left(5x-20\right)
Rewrite x^{2}+x-20 as \left(x^{2}-4x\right)+\left(5x-20\right).
x\left(x-4\right)+5\left(x-4\right)
Factor out x in the first and 5 in the second group.
\left(x-4\right)\left(x+5\right)
Factor out common term x-4 by using distributive property.
x=4 x=-5
To find equation solutions, solve x-4=0 and x+5=0.
\left(x-2\right)\times 5+\left(x-2\right)^{2}-14=0
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)^{2}, the least common multiple of x-2,x^{2}-4x+4.
5x-10+\left(x-2\right)^{2}-14=0
Use the distributive property to multiply x-2 by 5.
5x-10+x^{2}-4x+4-14=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x-10+x^{2}+4-14=0
Combine 5x and -4x to get x.
x-6+x^{2}-14=0
Add -10 and 4 to get -6.
x-20+x^{2}=0
Subtract 14 from -6 to get -20.
x^{2}+x-20=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{-1±\sqrt{1^{2}-4\left(-20\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 1 for b, and -20 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±\sqrt{1-4\left(-20\right)}}{2}
Square 1.
x=\frac{-1±\sqrt{1+80}}{2}
Multiply -4 times -20.
x=\frac{-1±\sqrt{81}}{2}
Add 1 to 80.
x=\frac{-1±9}{2}
Take the square root of 81.
x=\frac{8}{2}
Now solve the equation x=\frac{-1±9}{2} when ± is plus. Add -1 to 9.
x=4
Divide 8 by 2.
x=-\frac{10}{2}
Now solve the equation x=\frac{-1±9}{2} when ± is minus. Subtract 9 from -1.
x=-5
Divide -10 by 2.
x=4 x=-5
The equation is now solved.
\left(x-2\right)\times 5+\left(x-2\right)^{2}-14=0
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)^{2}, the least common multiple of x-2,x^{2}-4x+4.
5x-10+\left(x-2\right)^{2}-14=0
Use the distributive property to multiply x-2 by 5.
5x-10+x^{2}-4x+4-14=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x-10+x^{2}+4-14=0
Combine 5x and -4x to get x.
x-6+x^{2}-14=0
Add -10 and 4 to get -6.
x-20+x^{2}=0
Subtract 14 from -6 to get -20.
x+x^{2}=20
Add 20 to both sides. Anything plus zero gives itself.
x^{2}+x=20
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.
x^{2}+x+\left(\frac{1}{2}\right)^{2}=20+\left(\frac{1}{2}\right)^{2}
Divide 1, the coefficient of the x term, by 2 to get \frac{1}{2}. Then add the square of \frac{1}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+x+\frac{1}{4}=20+\frac{1}{4}
Square \frac{1}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}+x+\frac{1}{4}=\frac{81}{4}
Add 20 to \frac{1}{4}.
\left(x+\frac{1}{2}\right)^{2}=\frac{81}{4}
Factor x^{2}+x+\frac{1}{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{1}{2}\right)^{2}}=\sqrt{\frac{81}{4}}
Take the square root of both sides of the equation.
x+\frac{1}{2}=\frac{9}{2} x+\frac{1}{2}=-\frac{9}{2}
Simplify.
x=4 x=-5
Subtract \frac{1}{2} from both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}