Solve for x
x=5
x = \frac{7}{2} = 3\frac{1}{2} = 3.5
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\left(x-4\right)\times 2+x-3=2\left(x-4\right)\left(x-3\right)
Variable x cannot be equal to any of the values 3,4 since division by zero is not defined. Multiply both sides of the equation by \left(x-4\right)\left(x-3\right), the least common multiple of x-3,x-4.
2x-8+x-3=2\left(x-4\right)\left(x-3\right)
Use the distributive property to multiply x-4 by 2.
3x-8-3=2\left(x-4\right)\left(x-3\right)
Combine 2x and x to get 3x.
3x-11=2\left(x-4\right)\left(x-3\right)
Subtract 3 from -8 to get -11.
3x-11=\left(2x-8\right)\left(x-3\right)
Use the distributive property to multiply 2 by x-4.
3x-11=2x^{2}-14x+24
Use the distributive property to multiply 2x-8 by x-3 and combine like terms.
3x-11-2x^{2}=-14x+24
Subtract 2x^{2} from both sides.
3x-11-2x^{2}+14x=24
Add 14x to both sides.
17x-11-2x^{2}=24
Combine 3x and 14x to get 17x.
17x-11-2x^{2}-24=0
Subtract 24 from both sides.
17x-35-2x^{2}=0
Subtract 24 from -11 to get -35.
-2x^{2}+17x-35=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{-17±\sqrt{17^{2}-4\left(-2\right)\left(-35\right)}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 17 for b, and -35 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-17±\sqrt{289-4\left(-2\right)\left(-35\right)}}{2\left(-2\right)}
Square 17.
x=\frac{-17±\sqrt{289+8\left(-35\right)}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{-17±\sqrt{289-280}}{2\left(-2\right)}
Multiply 8 times -35.
x=\frac{-17±\sqrt{9}}{2\left(-2\right)}
Add 289 to -280.
x=\frac{-17±3}{2\left(-2\right)}
Take the square root of 9.
x=\frac{-17±3}{-4}
Multiply 2 times -2.
x=-\frac{14}{-4}
Now solve the equation x=\frac{-17±3}{-4} when ± is plus. Add -17 to 3.
x=\frac{7}{2}
Reduce the fraction \frac{-14}{-4} to lowest terms by extracting and canceling out 2.
x=-\frac{20}{-4}
Now solve the equation x=\frac{-17±3}{-4} when ± is minus. Subtract 3 from -17.
x=5
Divide -20 by -4.
x=\frac{7}{2} x=5
The equation is now solved.
\left(x-4\right)\times 2+x-3=2\left(x-4\right)\left(x-3\right)
Variable x cannot be equal to any of the values 3,4 since division by zero is not defined. Multiply both sides of the equation by \left(x-4\right)\left(x-3\right), the least common multiple of x-3,x-4.
2x-8+x-3=2\left(x-4\right)\left(x-3\right)
Use the distributive property to multiply x-4 by 2.
3x-8-3=2\left(x-4\right)\left(x-3\right)
Combine 2x and x to get 3x.
3x-11=2\left(x-4\right)\left(x-3\right)
Subtract 3 from -8 to get -11.
3x-11=\left(2x-8\right)\left(x-3\right)
Use the distributive property to multiply 2 by x-4.
3x-11=2x^{2}-14x+24
Use the distributive property to multiply 2x-8 by x-3 and combine like terms.
3x-11-2x^{2}=-14x+24
Subtract 2x^{2} from both sides.
3x-11-2x^{2}+14x=24
Add 14x to both sides.
17x-11-2x^{2}=24
Combine 3x and 14x to get 17x.
17x-2x^{2}=24+11
Add 11 to both sides.
17x-2x^{2}=35
Add 24 and 11 to get 35.
-2x^{2}+17x=35
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{-2x^{2}+17x}{-2}=\frac{35}{-2}
Divide both sides by -2.
x^{2}+\frac{17}{-2}x=\frac{35}{-2}
Dividing by -2 undoes the multiplication by -2.
x^{2}-\frac{17}{2}x=\frac{35}{-2}
Divide 17 by -2.
x^{2}-\frac{17}{2}x=-\frac{35}{2}
Divide 35 by -2.
x^{2}-\frac{17}{2}x+\left(-\frac{17}{4}\right)^{2}=-\frac{35}{2}+\left(-\frac{17}{4}\right)^{2}
Divide -\frac{17}{2}, the coefficient of the x term, by 2 to get -\frac{17}{4}. Then add the square of -\frac{17}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{17}{2}x+\frac{289}{16}=-\frac{35}{2}+\frac{289}{16}
Square -\frac{17}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{17}{2}x+\frac{289}{16}=\frac{9}{16}
Add -\frac{35}{2} to \frac{289}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{17}{4}\right)^{2}=\frac{9}{16}
Factor x^{2}-\frac{17}{2}x+\frac{289}{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-\frac{17}{4}\right)^{2}}=\sqrt{\frac{9}{16}}
Take the square root of both sides of the equation.
x-\frac{17}{4}=\frac{3}{4} x-\frac{17}{4}=-\frac{3}{4}
Simplify.
x=5 x=\frac{7}{2}
Add \frac{17}{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}