Solve for a
a=\frac{b\left(b+1\right)}{2}
b\neq -1\text{ and }b\neq 0
Solve for b
b=\frac{-\sqrt{8a+1}-1}{2}
b=\frac{\sqrt{8a+1}-1}{2}\text{, }a\neq 0\text{ and }a\geq -\frac{1}{8}
Share
Copied to clipboard
a\left(a+1\right)=a\left(a-1\right)+b\left(b+1\right)
Variable a cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by ab, the least common multiple of b,a.
a^{2}+a=a\left(a-1\right)+b\left(b+1\right)
Use the distributive property to multiply a by a+1.
a^{2}+a=a^{2}-a+b\left(b+1\right)
Use the distributive property to multiply a by a-1.
a^{2}+a=a^{2}-a+b^{2}+b
Use the distributive property to multiply b by b+1.
a^{2}+a-a^{2}=-a+b^{2}+b
Subtract a^{2} from both sides.
a=-a+b^{2}+b
Combine a^{2} and -a^{2} to get 0.
a+a=b^{2}+b
Add a to both sides.
2a=b^{2}+b
Combine a and a to get 2a.
\frac{2a}{2}=\frac{b\left(b+1\right)}{2}
Divide both sides by 2.
a=\frac{b\left(b+1\right)}{2}
Dividing by 2 undoes the multiplication by 2.
a=\frac{b\left(b+1\right)}{2}\text{, }a\neq 0
Variable a cannot be equal to 0.
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}