Evaluate
\frac{7\left(x+5\right)}{x\left(21-x\right)}
Expand
-\frac{7\left(x+5\right)}{x\left(x-21\right)}
Graph
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\frac{\frac{5}{x}+\frac{x}{x}}{3-\frac{x}{7}}
To add or subtract expressions, expand them to make their denominators the same. Multiply 1 times \frac{x}{x}.
\frac{\frac{5+x}{x}}{3-\frac{x}{7}}
Since \frac{5}{x} and \frac{x}{x} have the same denominator, add them by adding their numerators.
\frac{\frac{5+x}{x}}{\frac{3\times 7}{7}-\frac{x}{7}}
To add or subtract expressions, expand them to make their denominators the same. Multiply 3 times \frac{7}{7}.
\frac{\frac{5+x}{x}}{\frac{3\times 7-x}{7}}
Since \frac{3\times 7}{7} and \frac{x}{7} have the same denominator, subtract them by subtracting their numerators.
\frac{\frac{5+x}{x}}{\frac{21-x}{7}}
Do the multiplications in 3\times 7-x.
\frac{\left(5+x\right)\times 7}{x\left(21-x\right)}
Divide \frac{5+x}{x} by \frac{21-x}{7} by multiplying \frac{5+x}{x} by the reciprocal of \frac{21-x}{7}.
\frac{35+7x}{x\left(21-x\right)}
Use the distributive property to multiply 5+x by 7.
\frac{35+7x}{21x-x^{2}}
Use the distributive property to multiply x by 21-x.
\frac{\frac{5}{x}+\frac{x}{x}}{3-\frac{x}{7}}
To add or subtract expressions, expand them to make their denominators the same. Multiply 1 times \frac{x}{x}.
\frac{\frac{5+x}{x}}{3-\frac{x}{7}}
Since \frac{5}{x} and \frac{x}{x} have the same denominator, add them by adding their numerators.
\frac{\frac{5+x}{x}}{\frac{3\times 7}{7}-\frac{x}{7}}
To add or subtract expressions, expand them to make their denominators the same. Multiply 3 times \frac{7}{7}.
\frac{\frac{5+x}{x}}{\frac{3\times 7-x}{7}}
Since \frac{3\times 7}{7} and \frac{x}{7} have the same denominator, subtract them by subtracting their numerators.
\frac{\frac{5+x}{x}}{\frac{21-x}{7}}
Do the multiplications in 3\times 7-x.
\frac{\left(5+x\right)\times 7}{x\left(21-x\right)}
Divide \frac{5+x}{x} by \frac{21-x}{7} by multiplying \frac{5+x}{x} by the reciprocal of \frac{21-x}{7}.
\frac{35+7x}{x\left(21-x\right)}
Use the distributive property to multiply 5+x by 7.
\frac{35+7x}{21x-x^{2}}
Use the distributive property to multiply x by 21-x.
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}