Solve for x
x = \frac{21}{5} = 4\frac{1}{5} = 4.2
Assign x
x≔\frac{21}{5}
Graph
Share
Copied to clipboard
x=\frac{3+\frac{3\times 5}{2}}{1+\frac{3}{2}}
Express \frac{3}{2}\times 5 as a single fraction.
x=\frac{3+\frac{15}{2}}{1+\frac{3}{2}}
Multiply 3 and 5 to get 15.
x=\frac{\frac{6}{2}+\frac{15}{2}}{1+\frac{3}{2}}
Convert 3 to fraction \frac{6}{2}.
x=\frac{\frac{6+15}{2}}{1+\frac{3}{2}}
Since \frac{6}{2} and \frac{15}{2} have the same denominator, add them by adding their numerators.
x=\frac{\frac{21}{2}}{1+\frac{3}{2}}
Add 6 and 15 to get 21.
x=\frac{\frac{21}{2}}{\frac{2}{2}+\frac{3}{2}}
Convert 1 to fraction \frac{2}{2}.
x=\frac{\frac{21}{2}}{\frac{2+3}{2}}
Since \frac{2}{2} and \frac{3}{2} have the same denominator, add them by adding their numerators.
x=\frac{\frac{21}{2}}{\frac{5}{2}}
Add 2 and 3 to get 5.
x=\frac{21}{2}\times \frac{2}{5}
Divide \frac{21}{2} by \frac{5}{2} by multiplying \frac{21}{2} by the reciprocal of \frac{5}{2}.
x=\frac{21\times 2}{2\times 5}
Multiply \frac{21}{2} times \frac{2}{5} by multiplying numerator times numerator and denominator times denominator.
x=\frac{21}{5}
Cancel out 2 in both numerator and denominator.
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}