Solve for x
x=8
x=10
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\left(x-5\right)\left(5x-5\right)=\left(2x+5\right)\left(2x-11\right)
Variable x cannot be equal to any of the values -\frac{5}{2},5 since division by zero is not defined. Multiply both sides of the equation by \left(x-5\right)\left(2x+5\right), the least common multiple of 2x+5,x-5.
5x^{2}-30x+25=\left(2x+5\right)\left(2x-11\right)
Use the distributive property to multiply x-5 by 5x-5 and combine like terms.
5x^{2}-30x+25=4x^{2}-12x-55
Use the distributive property to multiply 2x+5 by 2x-11 and combine like terms.
5x^{2}-30x+25-4x^{2}=-12x-55
Subtract 4x^{2} from both sides.
x^{2}-30x+25=-12x-55
Combine 5x^{2} and -4x^{2} to get x^{2}.
x^{2}-30x+25+12x=-55
Add 12x to both sides.
x^{2}-18x+25=-55
Combine -30x and 12x to get -18x.
x^{2}-18x+25+55=0
Add 55 to both sides.
x^{2}-18x+80=0
Add 25 and 55 to get 80.
x=\frac{-\left(-18\right)±\sqrt{\left(-18\right)^{2}-4\times 80}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -18 for b, and 80 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-18\right)±\sqrt{324-4\times 80}}{2}
Square -18.
x=\frac{-\left(-18\right)±\sqrt{324-320}}{2}
Multiply -4 times 80.
x=\frac{-\left(-18\right)±\sqrt{4}}{2}
Add 324 to -320.
x=\frac{-\left(-18\right)±2}{2}
Take the square root of 4.
x=\frac{18±2}{2}
The opposite of -18 is 18.
x=\frac{20}{2}
Now solve the equation x=\frac{18±2}{2} when ± is plus. Add 18 to 2.
x=10
Divide 20 by 2.
x=\frac{16}{2}
Now solve the equation x=\frac{18±2}{2} when ± is minus. Subtract 2 from 18.
x=8
Divide 16 by 2.
x=10 x=8
The equation is now solved.
\left(x-5\right)\left(5x-5\right)=\left(2x+5\right)\left(2x-11\right)
Variable x cannot be equal to any of the values -\frac{5}{2},5 since division by zero is not defined. Multiply both sides of the equation by \left(x-5\right)\left(2x+5\right), the least common multiple of 2x+5,x-5.
5x^{2}-30x+25=\left(2x+5\right)\left(2x-11\right)
Use the distributive property to multiply x-5 by 5x-5 and combine like terms.
5x^{2}-30x+25=4x^{2}-12x-55
Use the distributive property to multiply 2x+5 by 2x-11 and combine like terms.
5x^{2}-30x+25-4x^{2}=-12x-55
Subtract 4x^{2} from both sides.
x^{2}-30x+25=-12x-55
Combine 5x^{2} and -4x^{2} to get x^{2}.
x^{2}-30x+25+12x=-55
Add 12x to both sides.
x^{2}-18x+25=-55
Combine -30x and 12x to get -18x.
x^{2}-18x=-55-25
Subtract 25 from both sides.
x^{2}-18x=-80
Subtract 25 from -55 to get -80.
x^{2}-18x+\left(-9\right)^{2}=-80+\left(-9\right)^{2}
Divide -18, the coefficient of the x term, by 2 to get -9. Then add the square of -9 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-18x+81=-80+81
Square -9.
x^{2}-18x+81=1
Add -80 to 81.
\left(x-9\right)^{2}=1
Factor x^{2}-18x+81. 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-9\right)^{2}}=\sqrt{1}
Take the square root of both sides of the equation.
x-9=1 x-9=-1
Simplify.
x=10 x=8
Add 9 to 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}