Solve for x
x=-2
x=0
Graph
Share
Copied to clipboard
1+x+1=\left(x+1\right)x+\left(x+1\right)\times 2
Variable x cannot be equal to -1 since division by zero is not defined. Multiply both sides of the equation by x+1.
2+x=\left(x+1\right)x+\left(x+1\right)\times 2
Add 1 and 1 to get 2.
2+x=x^{2}+x+\left(x+1\right)\times 2
Use the distributive property to multiply x+1 by x.
2+x=x^{2}+x+2x+2
Use the distributive property to multiply x+1 by 2.
2+x=x^{2}+3x+2
Combine x and 2x to get 3x.
2+x-x^{2}=3x+2
Subtract x^{2} from both sides.
2+x-x^{2}-3x=2
Subtract 3x from both sides.
2-2x-x^{2}=2
Combine x and -3x to get -2x.
2-2x-x^{2}-2=0
Subtract 2 from both sides.
-2x-x^{2}=0
Subtract 2 from 2 to get 0.
-x^{2}-2x=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(-2\right)±\sqrt{\left(-2\right)^{2}}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, -2 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-2\right)±2}{2\left(-1\right)}
Take the square root of \left(-2\right)^{2}.
x=\frac{2±2}{2\left(-1\right)}
The opposite of -2 is 2.
x=\frac{2±2}{-2}
Multiply 2 times -1.
x=\frac{4}{-2}
Now solve the equation x=\frac{2±2}{-2} when ± is plus. Add 2 to 2.
x=-2
Divide 4 by -2.
x=\frac{0}{-2}
Now solve the equation x=\frac{2±2}{-2} when ± is minus. Subtract 2 from 2.
x=0
Divide 0 by -2.
x=-2 x=0
The equation is now solved.
1+x+1=\left(x+1\right)x+\left(x+1\right)\times 2
Variable x cannot be equal to -1 since division by zero is not defined. Multiply both sides of the equation by x+1.
2+x=\left(x+1\right)x+\left(x+1\right)\times 2
Add 1 and 1 to get 2.
2+x=x^{2}+x+\left(x+1\right)\times 2
Use the distributive property to multiply x+1 by x.
2+x=x^{2}+x+2x+2
Use the distributive property to multiply x+1 by 2.
2+x=x^{2}+3x+2
Combine x and 2x to get 3x.
2+x-x^{2}=3x+2
Subtract x^{2} from both sides.
2+x-x^{2}-3x=2
Subtract 3x from both sides.
2-2x-x^{2}=2
Combine x and -3x to get -2x.
-2x-x^{2}=2-2
Subtract 2 from both sides.
-2x-x^{2}=0
Subtract 2 from 2 to get 0.
-x^{2}-2x=0
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{-x^{2}-2x}{-1}=\frac{0}{-1}
Divide both sides by -1.
x^{2}+\left(-\frac{2}{-1}\right)x=\frac{0}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}+2x=\frac{0}{-1}
Divide -2 by -1.
x^{2}+2x=0
Divide 0 by -1.
x^{2}+2x+1^{2}=1^{2}
Divide 2, the coefficient of the x term, by 2 to get 1. Then add the square of 1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+2x+1=1
Square 1.
\left(x+1\right)^{2}=1
Factor x^{2}+2x+1. 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+1\right)^{2}}=\sqrt{1}
Take the square root of both sides of the equation.
x+1=1 x+1=-1
Simplify.
x=0 x=-2
Subtract 1 from 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}