Solve for x
x=-2
x=30
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Quadratic Equation
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x - 4 [ 3 ( x - 2 ) + 11 ] = - \frac { x } { 3 } ( x + 5 )
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3x-12\left(3\left(x-2\right)+11\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Multiply both sides of the equation by 3.
3x-12\left(3x-6+11\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Use the distributive property to multiply 3 by x-2.
3x-12\left(3x+5\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Add -6 and 11 to get 5.
3x-36x-60=3\left(-\frac{x}{3}\right)\left(x+5\right)
Use the distributive property to multiply -12 by 3x+5.
-33x-60=3\left(-\frac{x}{3}\right)\left(x+5\right)
Combine 3x and -36x to get -33x.
-33x-60=\frac{-3x}{3}\left(x+5\right)
Express 3\left(-\frac{x}{3}\right) as a single fraction.
-33x-60=-x\left(x+5\right)
Cancel out 3 and 3.
-33x-60=-x^{2}-5x
Use the distributive property to multiply -x by x+5.
-33x-60+x^{2}=-5x
Add x^{2} to both sides.
-33x-60+x^{2}+5x=0
Add 5x to both sides.
-28x-60+x^{2}=0
Combine -33x and 5x to get -28x.
x^{2}-28x-60=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-28 ab=-60
To solve the equation, factor x^{2}-28x-60 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,-60 2,-30 3,-20 4,-15 5,-12 6,-10
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 -60.
1-60=-59 2-30=-28 3-20=-17 4-15=-11 5-12=-7 6-10=-4
Calculate the sum for each pair.
a=-30 b=2
The solution is the pair that gives sum -28.
\left(x-30\right)\left(x+2\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=30 x=-2
To find equation solutions, solve x-30=0 and x+2=0.
3x-12\left(3\left(x-2\right)+11\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Multiply both sides of the equation by 3.
3x-12\left(3x-6+11\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Use the distributive property to multiply 3 by x-2.
3x-12\left(3x+5\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Add -6 and 11 to get 5.
3x-36x-60=3\left(-\frac{x}{3}\right)\left(x+5\right)
Use the distributive property to multiply -12 by 3x+5.
-33x-60=3\left(-\frac{x}{3}\right)\left(x+5\right)
Combine 3x and -36x to get -33x.
-33x-60=\frac{-3x}{3}\left(x+5\right)
Express 3\left(-\frac{x}{3}\right) as a single fraction.
-33x-60=-x\left(x+5\right)
Cancel out 3 and 3.
-33x-60=-x^{2}-5x
Use the distributive property to multiply -x by x+5.
-33x-60+x^{2}=-5x
Add x^{2} to both sides.
-33x-60+x^{2}+5x=0
Add 5x to both sides.
-28x-60+x^{2}=0
Combine -33x and 5x to get -28x.
x^{2}-28x-60=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-28 ab=1\left(-60\right)=-60
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-60. To find a and b, set up a system to be solved.
1,-60 2,-30 3,-20 4,-15 5,-12 6,-10
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 -60.
1-60=-59 2-30=-28 3-20=-17 4-15=-11 5-12=-7 6-10=-4
Calculate the sum for each pair.
a=-30 b=2
The solution is the pair that gives sum -28.
\left(x^{2}-30x\right)+\left(2x-60\right)
Rewrite x^{2}-28x-60 as \left(x^{2}-30x\right)+\left(2x-60\right).
x\left(x-30\right)+2\left(x-30\right)
Factor out x in the first and 2 in the second group.
\left(x-30\right)\left(x+2\right)
Factor out common term x-30 by using distributive property.
x=30 x=-2
To find equation solutions, solve x-30=0 and x+2=0.
3x-12\left(3\left(x-2\right)+11\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Multiply both sides of the equation by 3.
3x-12\left(3x-6+11\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Use the distributive property to multiply 3 by x-2.
3x-12\left(3x+5\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Add -6 and 11 to get 5.
3x-36x-60=3\left(-\frac{x}{3}\right)\left(x+5\right)
Use the distributive property to multiply -12 by 3x+5.
-33x-60=3\left(-\frac{x}{3}\right)\left(x+5\right)
Combine 3x and -36x to get -33x.
-33x-60=\frac{-3x}{3}\left(x+5\right)
Express 3\left(-\frac{x}{3}\right) as a single fraction.
-33x-60=-x\left(x+5\right)
Cancel out 3 and 3.
-33x-60=-x^{2}-5x
Use the distributive property to multiply -x by x+5.
-33x-60+x^{2}=-5x
Add x^{2} to both sides.
-33x-60+x^{2}+5x=0
Add 5x to both sides.
-28x-60+x^{2}=0
Combine -33x and 5x to get -28x.
x^{2}-28x-60=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(-28\right)±\sqrt{\left(-28\right)^{2}-4\left(-60\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -28 for b, and -60 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-28\right)±\sqrt{784-4\left(-60\right)}}{2}
Square -28.
x=\frac{-\left(-28\right)±\sqrt{784+240}}{2}
Multiply -4 times -60.
x=\frac{-\left(-28\right)±\sqrt{1024}}{2}
Add 784 to 240.
x=\frac{-\left(-28\right)±32}{2}
Take the square root of 1024.
x=\frac{28±32}{2}
The opposite of -28 is 28.
x=\frac{60}{2}
Now solve the equation x=\frac{28±32}{2} when ± is plus. Add 28 to 32.
x=30
Divide 60 by 2.
x=-\frac{4}{2}
Now solve the equation x=\frac{28±32}{2} when ± is minus. Subtract 32 from 28.
x=-2
Divide -4 by 2.
x=30 x=-2
The equation is now solved.
3x-12\left(3\left(x-2\right)+11\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Multiply both sides of the equation by 3.
3x-12\left(3x-6+11\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Use the distributive property to multiply 3 by x-2.
3x-12\left(3x+5\right)=3\left(-\frac{x}{3}\right)\left(x+5\right)
Add -6 and 11 to get 5.
3x-36x-60=3\left(-\frac{x}{3}\right)\left(x+5\right)
Use the distributive property to multiply -12 by 3x+5.
-33x-60=3\left(-\frac{x}{3}\right)\left(x+5\right)
Combine 3x and -36x to get -33x.
-33x-60=\frac{-3x}{3}\left(x+5\right)
Express 3\left(-\frac{x}{3}\right) as a single fraction.
-33x-60=-x\left(x+5\right)
Cancel out 3 and 3.
-33x-60=-x^{2}-5x
Use the distributive property to multiply -x by x+5.
-33x-60+x^{2}=-5x
Add x^{2} to both sides.
-33x-60+x^{2}+5x=0
Add 5x to both sides.
-28x-60+x^{2}=0
Combine -33x and 5x to get -28x.
-28x+x^{2}=60
Add 60 to both sides. Anything plus zero gives itself.
x^{2}-28x=60
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}-28x+\left(-14\right)^{2}=60+\left(-14\right)^{2}
Divide -28, the coefficient of the x term, by 2 to get -14. Then add the square of -14 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-28x+196=60+196
Square -14.
x^{2}-28x+196=256
Add 60 to 196.
\left(x-14\right)^{2}=256
Factor x^{2}-28x+196. 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-14\right)^{2}}=\sqrt{256}
Take the square root of both sides of the equation.
x-14=16 x-14=-16
Simplify.
x=30 x=-2
Add 14 to both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
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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}