Solve for x
x=1
x=5
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\left(x-3\right)^{2}-4\left(x-2\right)^{2}=8\left(1-x\right)
Multiply both sides of the equation by 16, the least common multiple of 16,4,2.
x^{2}-6x+9-4\left(x-2\right)^{2}=8\left(1-x\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-3\right)^{2}.
x^{2}-6x+9-4\left(x^{2}-4x+4\right)=8\left(1-x\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x^{2}-6x+9-4x^{2}+16x-16=8\left(1-x\right)
Use the distributive property to multiply -4 by x^{2}-4x+4.
-3x^{2}-6x+9+16x-16=8\left(1-x\right)
Combine x^{2} and -4x^{2} to get -3x^{2}.
-3x^{2}+10x+9-16=8\left(1-x\right)
Combine -6x and 16x to get 10x.
-3x^{2}+10x-7=8\left(1-x\right)
Subtract 16 from 9 to get -7.
-3x^{2}+10x-7=8-8x
Use the distributive property to multiply 8 by 1-x.
-3x^{2}+10x-7-8=-8x
Subtract 8 from both sides.
-3x^{2}+10x-15=-8x
Subtract 8 from -7 to get -15.
-3x^{2}+10x-15+8x=0
Add 8x to both sides.
-3x^{2}+18x-15=0
Combine 10x and 8x to get 18x.
-x^{2}+6x-5=0
Divide both sides by 3.
a+b=6 ab=-\left(-5\right)=5
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -x^{2}+ax+bx-5. To find a and b, set up a system to be solved.
a=5 b=1
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. The only such pair is the system solution.
\left(-x^{2}+5x\right)+\left(x-5\right)
Rewrite -x^{2}+6x-5 as \left(-x^{2}+5x\right)+\left(x-5\right).
-x\left(x-5\right)+x-5
Factor out -x in -x^{2}+5x.
\left(x-5\right)\left(-x+1\right)
Factor out common term x-5 by using distributive property.
x=5 x=1
To find equation solutions, solve x-5=0 and -x+1=0.
\left(x-3\right)^{2}-4\left(x-2\right)^{2}=8\left(1-x\right)
Multiply both sides of the equation by 16, the least common multiple of 16,4,2.
x^{2}-6x+9-4\left(x-2\right)^{2}=8\left(1-x\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-3\right)^{2}.
x^{2}-6x+9-4\left(x^{2}-4x+4\right)=8\left(1-x\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x^{2}-6x+9-4x^{2}+16x-16=8\left(1-x\right)
Use the distributive property to multiply -4 by x^{2}-4x+4.
-3x^{2}-6x+9+16x-16=8\left(1-x\right)
Combine x^{2} and -4x^{2} to get -3x^{2}.
-3x^{2}+10x+9-16=8\left(1-x\right)
Combine -6x and 16x to get 10x.
-3x^{2}+10x-7=8\left(1-x\right)
Subtract 16 from 9 to get -7.
-3x^{2}+10x-7=8-8x
Use the distributive property to multiply 8 by 1-x.
-3x^{2}+10x-7-8=-8x
Subtract 8 from both sides.
-3x^{2}+10x-15=-8x
Subtract 8 from -7 to get -15.
-3x^{2}+10x-15+8x=0
Add 8x to both sides.
-3x^{2}+18x-15=0
Combine 10x and 8x to get 18x.
x=\frac{-18±\sqrt{18^{2}-4\left(-3\right)\left(-15\right)}}{2\left(-3\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -3 for a, 18 for b, and -15 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-18±\sqrt{324-4\left(-3\right)\left(-15\right)}}{2\left(-3\right)}
Square 18.
x=\frac{-18±\sqrt{324+12\left(-15\right)}}{2\left(-3\right)}
Multiply -4 times -3.
x=\frac{-18±\sqrt{324-180}}{2\left(-3\right)}
Multiply 12 times -15.
x=\frac{-18±\sqrt{144}}{2\left(-3\right)}
Add 324 to -180.
x=\frac{-18±12}{2\left(-3\right)}
Take the square root of 144.
x=\frac{-18±12}{-6}
Multiply 2 times -3.
x=-\frac{6}{-6}
Now solve the equation x=\frac{-18±12}{-6} when ± is plus. Add -18 to 12.
x=1
Divide -6 by -6.
x=-\frac{30}{-6}
Now solve the equation x=\frac{-18±12}{-6} when ± is minus. Subtract 12 from -18.
x=5
Divide -30 by -6.
x=1 x=5
The equation is now solved.
\left(x-3\right)^{2}-4\left(x-2\right)^{2}=8\left(1-x\right)
Multiply both sides of the equation by 16, the least common multiple of 16,4,2.
x^{2}-6x+9-4\left(x-2\right)^{2}=8\left(1-x\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-3\right)^{2}.
x^{2}-6x+9-4\left(x^{2}-4x+4\right)=8\left(1-x\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x^{2}-6x+9-4x^{2}+16x-16=8\left(1-x\right)
Use the distributive property to multiply -4 by x^{2}-4x+4.
-3x^{2}-6x+9+16x-16=8\left(1-x\right)
Combine x^{2} and -4x^{2} to get -3x^{2}.
-3x^{2}+10x+9-16=8\left(1-x\right)
Combine -6x and 16x to get 10x.
-3x^{2}+10x-7=8\left(1-x\right)
Subtract 16 from 9 to get -7.
-3x^{2}+10x-7=8-8x
Use the distributive property to multiply 8 by 1-x.
-3x^{2}+10x-7+8x=8
Add 8x to both sides.
-3x^{2}+18x-7=8
Combine 10x and 8x to get 18x.
-3x^{2}+18x=8+7
Add 7 to both sides.
-3x^{2}+18x=15
Add 8 and 7 to get 15.
\frac{-3x^{2}+18x}{-3}=\frac{15}{-3}
Divide both sides by -3.
x^{2}+\frac{18}{-3}x=\frac{15}{-3}
Dividing by -3 undoes the multiplication by -3.
x^{2}-6x=\frac{15}{-3}
Divide 18 by -3.
x^{2}-6x=-5
Divide 15 by -3.
x^{2}-6x+\left(-3\right)^{2}=-5+\left(-3\right)^{2}
Divide -6, the coefficient of the x term, by 2 to get -3. Then add the square of -3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-6x+9=-5+9
Square -3.
x^{2}-6x+9=4
Add -5 to 9.
\left(x-3\right)^{2}=4
Factor x^{2}-6x+9. 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-3\right)^{2}}=\sqrt{4}
Take the square root of both sides of the equation.
x-3=2 x-3=-2
Simplify.
x=5 x=1
Add 3 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}