Solve for x
x=-1
x=4
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Quiz
Polynomial
5 problems similar to:
\frac{ 5-x }{ { x }^{ 2 } -4x+4 } = \frac{ x-1 }{ { x }^{ 2 } -4 }
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\left(x+2\right)\left(5-x\right)=\left(x-2\right)\left(x-1\right)
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x+2\right)\left(x-2\right)^{2}, the least common multiple of x^{2}-4x+4,x^{2}-4.
3x-x^{2}+10=\left(x-2\right)\left(x-1\right)
Use the distributive property to multiply x+2 by 5-x and combine like terms.
3x-x^{2}+10=x^{2}-3x+2
Use the distributive property to multiply x-2 by x-1 and combine like terms.
3x-x^{2}+10-x^{2}=-3x+2
Subtract x^{2} from both sides.
3x-2x^{2}+10=-3x+2
Combine -x^{2} and -x^{2} to get -2x^{2}.
3x-2x^{2}+10+3x=2
Add 3x to both sides.
6x-2x^{2}+10=2
Combine 3x and 3x to get 6x.
6x-2x^{2}+10-2=0
Subtract 2 from both sides.
6x-2x^{2}+8=0
Subtract 2 from 10 to get 8.
3x-x^{2}+4=0
Divide both sides by 2.
-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=-4=-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 positive, the positive number has greater absolute value than the negative. 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)-\left(x-4\right)
Factor out -x in the first and -1 in the second group.
\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.
\left(x+2\right)\left(5-x\right)=\left(x-2\right)\left(x-1\right)
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x+2\right)\left(x-2\right)^{2}, the least common multiple of x^{2}-4x+4,x^{2}-4.
3x-x^{2}+10=\left(x-2\right)\left(x-1\right)
Use the distributive property to multiply x+2 by 5-x and combine like terms.
3x-x^{2}+10=x^{2}-3x+2
Use the distributive property to multiply x-2 by x-1 and combine like terms.
3x-x^{2}+10-x^{2}=-3x+2
Subtract x^{2} from both sides.
3x-2x^{2}+10=-3x+2
Combine -x^{2} and -x^{2} to get -2x^{2}.
3x-2x^{2}+10+3x=2
Add 3x to both sides.
6x-2x^{2}+10=2
Combine 3x and 3x to get 6x.
6x-2x^{2}+10-2=0
Subtract 2 from both sides.
6x-2x^{2}+8=0
Subtract 2 from 10 to get 8.
-2x^{2}+6x+8=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{-6±\sqrt{6^{2}-4\left(-2\right)\times 8}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 6 for b, and 8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-6±\sqrt{36-4\left(-2\right)\times 8}}{2\left(-2\right)}
Square 6.
x=\frac{-6±\sqrt{36+8\times 8}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{-6±\sqrt{36+64}}{2\left(-2\right)}
Multiply 8 times 8.
x=\frac{-6±\sqrt{100}}{2\left(-2\right)}
Add 36 to 64.
x=\frac{-6±10}{2\left(-2\right)}
Take the square root of 100.
x=\frac{-6±10}{-4}
Multiply 2 times -2.
x=\frac{4}{-4}
Now solve the equation x=\frac{-6±10}{-4} when ± is plus. Add -6 to 10.
x=-1
Divide 4 by -4.
x=-\frac{16}{-4}
Now solve the equation x=\frac{-6±10}{-4} when ± is minus. Subtract 10 from -6.
x=4
Divide -16 by -4.
x=-1 x=4
The equation is now solved.
\left(x+2\right)\left(5-x\right)=\left(x-2\right)\left(x-1\right)
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x+2\right)\left(x-2\right)^{2}, the least common multiple of x^{2}-4x+4,x^{2}-4.
3x-x^{2}+10=\left(x-2\right)\left(x-1\right)
Use the distributive property to multiply x+2 by 5-x and combine like terms.
3x-x^{2}+10=x^{2}-3x+2
Use the distributive property to multiply x-2 by x-1 and combine like terms.
3x-x^{2}+10-x^{2}=-3x+2
Subtract x^{2} from both sides.
3x-2x^{2}+10=-3x+2
Combine -x^{2} and -x^{2} to get -2x^{2}.
3x-2x^{2}+10+3x=2
Add 3x to both sides.
6x-2x^{2}+10=2
Combine 3x and 3x to get 6x.
6x-2x^{2}=2-10
Subtract 10 from both sides.
6x-2x^{2}=-8
Subtract 10 from 2 to get -8.
-2x^{2}+6x=-8
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}+6x}{-2}=-\frac{8}{-2}
Divide both sides by -2.
x^{2}+\frac{6}{-2}x=-\frac{8}{-2}
Dividing by -2 undoes the multiplication by -2.
x^{2}-3x=-\frac{8}{-2}
Divide 6 by -2.
x^{2}-3x=4
Divide -8 by -2.
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}