Solve for x
x=1
x=7
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2x^{2}-13x+20-7=\left(x-2\right)\left(x-3\right)
Use the distributive property to multiply 2x-5 by x-4 and combine like terms.
2x^{2}-13x+13=\left(x-2\right)\left(x-3\right)
Subtract 7 from 20 to get 13.
2x^{2}-13x+13=x^{2}-5x+6
Use the distributive property to multiply x-2 by x-3 and combine like terms.
2x^{2}-13x+13-x^{2}=-5x+6
Subtract x^{2} from both sides.
x^{2}-13x+13=-5x+6
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}-13x+13+5x=6
Add 5x to both sides.
x^{2}-8x+13=6
Combine -13x and 5x to get -8x.
x^{2}-8x+13-6=0
Subtract 6 from both sides.
x^{2}-8x+7=0
Subtract 6 from 13 to get 7.
x=\frac{-\left(-8\right)±\sqrt{\left(-8\right)^{2}-4\times 7}}{2}
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{-\left(-8\right)±\sqrt{64-4\times 7}}{2}
Square -8.
x=\frac{-\left(-8\right)±\sqrt{64-28}}{2}
Multiply -4 times 7.
x=\frac{-\left(-8\right)±\sqrt{36}}{2}
Add 64 to -28.
x=\frac{-\left(-8\right)±6}{2}
Take the square root of 36.
x=\frac{8±6}{2}
The opposite of -8 is 8.
x=\frac{14}{2}
Now solve the equation x=\frac{8±6}{2} when ± is plus. Add 8 to 6.
x=7
Divide 14 by 2.
x=\frac{2}{2}
Now solve the equation x=\frac{8±6}{2} when ± is minus. Subtract 6 from 8.
x=1
Divide 2 by 2.
x=7 x=1
The equation is now solved.
2x^{2}-13x+20-7=\left(x-2\right)\left(x-3\right)
Use the distributive property to multiply 2x-5 by x-4 and combine like terms.
2x^{2}-13x+13=\left(x-2\right)\left(x-3\right)
Subtract 7 from 20 to get 13.
2x^{2}-13x+13=x^{2}-5x+6
Use the distributive property to multiply x-2 by x-3 and combine like terms.
2x^{2}-13x+13-x^{2}=-5x+6
Subtract x^{2} from both sides.
x^{2}-13x+13=-5x+6
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}-13x+13+5x=6
Add 5x to both sides.
x^{2}-8x+13=6
Combine -13x and 5x to get -8x.
x^{2}-8x=6-13
Subtract 13 from both sides.
x^{2}-8x=-7
Subtract 13 from 6 to get -7.
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.
Examples
Quadratic equation
{ 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}