Solve for x
x=-1
x=4
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2\left(x^{2}-10\right)+3x\left(x-3\right)=6x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 6x, the least common multiple of 3x,2.
2x^{2}-20+3x\left(x-3\right)=6x
Use the distributive property to multiply 2 by x^{2}-10.
2x^{2}-20+3x^{2}-9x=6x
Use the distributive property to multiply 3x by x-3.
5x^{2}-20-9x=6x
Combine 2x^{2} and 3x^{2} to get 5x^{2}.
5x^{2}-20-9x-6x=0
Subtract 6x from both sides.
5x^{2}-20-15x=0
Combine -9x and -6x to get -15x.
x^{2}-4-3x=0
Divide both sides by 5.
x^{2}-3x-4=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-3 ab=1\left(-4\right)=-4
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-4. To find a and b, set up a system to be solved.
1,-4 2,-2
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -4.
1-4=-3 2-2=0
Calculate the sum for each pair.
a=-4 b=1
The solution is the pair that gives sum -3.
\left(x^{2}-4x\right)+\left(x-4\right)
Rewrite x^{2}-3x-4 as \left(x^{2}-4x\right)+\left(x-4\right).
x\left(x-4\right)+x-4
Factor out x in x^{2}-4x.
\left(x-4\right)\left(x+1\right)
Factor out common term x-4 by using distributive property.
x=4 x=-1
To find equation solutions, solve x-4=0 and x+1=0.
2\left(x^{2}-10\right)+3x\left(x-3\right)=6x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 6x, the least common multiple of 3x,2.
2x^{2}-20+3x\left(x-3\right)=6x
Use the distributive property to multiply 2 by x^{2}-10.
2x^{2}-20+3x^{2}-9x=6x
Use the distributive property to multiply 3x by x-3.
5x^{2}-20-9x=6x
Combine 2x^{2} and 3x^{2} to get 5x^{2}.
5x^{2}-20-9x-6x=0
Subtract 6x from both sides.
5x^{2}-20-15x=0
Combine -9x and -6x to get -15x.
5x^{2}-15x-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{-\left(-15\right)±\sqrt{\left(-15\right)^{2}-4\times 5\left(-20\right)}}{2\times 5}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 5 for a, -15 for b, and -20 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-15\right)±\sqrt{225-4\times 5\left(-20\right)}}{2\times 5}
Square -15.
x=\frac{-\left(-15\right)±\sqrt{225-20\left(-20\right)}}{2\times 5}
Multiply -4 times 5.
x=\frac{-\left(-15\right)±\sqrt{225+400}}{2\times 5}
Multiply -20 times -20.
x=\frac{-\left(-15\right)±\sqrt{625}}{2\times 5}
Add 225 to 400.
x=\frac{-\left(-15\right)±25}{2\times 5}
Take the square root of 625.
x=\frac{15±25}{2\times 5}
The opposite of -15 is 15.
x=\frac{15±25}{10}
Multiply 2 times 5.
x=\frac{40}{10}
Now solve the equation x=\frac{15±25}{10} when ± is plus. Add 15 to 25.
x=4
Divide 40 by 10.
x=-\frac{10}{10}
Now solve the equation x=\frac{15±25}{10} when ± is minus. Subtract 25 from 15.
x=-1
Divide -10 by 10.
x=4 x=-1
The equation is now solved.
2\left(x^{2}-10\right)+3x\left(x-3\right)=6x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 6x, the least common multiple of 3x,2.
2x^{2}-20+3x\left(x-3\right)=6x
Use the distributive property to multiply 2 by x^{2}-10.
2x^{2}-20+3x^{2}-9x=6x
Use the distributive property to multiply 3x by x-3.
5x^{2}-20-9x=6x
Combine 2x^{2} and 3x^{2} to get 5x^{2}.
5x^{2}-20-9x-6x=0
Subtract 6x from both sides.
5x^{2}-20-15x=0
Combine -9x and -6x to get -15x.
5x^{2}-15x=20
Add 20 to both sides. Anything plus zero gives itself.
\frac{5x^{2}-15x}{5}=\frac{20}{5}
Divide both sides by 5.
x^{2}+\left(-\frac{15}{5}\right)x=\frac{20}{5}
Dividing by 5 undoes the multiplication by 5.
x^{2}-3x=\frac{20}{5}
Divide -15 by 5.
x^{2}-3x=4
Divide 20 by 5.
x^{2}-3x+\left(-\frac{3}{2}\right)^{2}=4+\left(-\frac{3}{2}\right)^{2}
Divide -3, the coefficient of the x term, by 2 to get -\frac{3}{2}. Then add the square of -\frac{3}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-3x+\frac{9}{4}=4+\frac{9}{4}
Square -\frac{3}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-3x+\frac{9}{4}=\frac{25}{4}
Add 4 to \frac{9}{4}.
\left(x-\frac{3}{2}\right)^{2}=\frac{25}{4}
Factor x^{2}-3x+\frac{9}{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{3}{2}\right)^{2}}=\sqrt{\frac{25}{4}}
Take the square root of both sides of the equation.
x-\frac{3}{2}=\frac{5}{2} x-\frac{3}{2}=-\frac{5}{2}
Simplify.
x=4 x=-1
Add \frac{3}{2} 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}