Solve for x
x=20
Graph
Share
Copied to clipboard
400\left(\frac{x}{5}-\frac{3}{4}\right)-4\times 3x=200\left(\frac{1}{5}+\frac{x}{4}\right)+20
Multiply both sides of the equation by 20, the least common multiple of 5,4.
400\left(\frac{4x}{20}-\frac{3\times 5}{20}\right)-4\times 3x=200\left(\frac{1}{5}+\frac{x}{4}\right)+20
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of 5 and 4 is 20. Multiply \frac{x}{5} times \frac{4}{4}. Multiply \frac{3}{4} times \frac{5}{5}.
400\times \frac{4x-3\times 5}{20}-4\times 3x=200\left(\frac{1}{5}+\frac{x}{4}\right)+20
Since \frac{4x}{20} and \frac{3\times 5}{20} have the same denominator, subtract them by subtracting their numerators.
400\times \frac{4x-15}{20}-4\times 3x=200\left(\frac{1}{5}+\frac{x}{4}\right)+20
Do the multiplications in 4x-3\times 5.
20\left(4x-15\right)-4\times 3x=200\left(\frac{1}{5}+\frac{x}{4}\right)+20
Cancel out 20, the greatest common factor in 400 and 20.
80x-300-4\times 3x=200\left(\frac{1}{5}+\frac{x}{4}\right)+20
Use the distributive property to multiply 20 by 4x-15.
80x-300-12x=200\left(\frac{1}{5}+\frac{x}{4}\right)+20
Multiply -4 and 3 to get -12.
68x-300=200\left(\frac{1}{5}+\frac{x}{4}\right)+20
Combine 80x and -12x to get 68x.
68x-300=200\left(\frac{4}{20}+\frac{5x}{20}\right)+20
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of 5 and 4 is 20. Multiply \frac{1}{5} times \frac{4}{4}. Multiply \frac{x}{4} times \frac{5}{5}.
68x-300=200\times \frac{4+5x}{20}+20
Since \frac{4}{20} and \frac{5x}{20} have the same denominator, add them by adding their numerators.
68x-300=10\left(4+5x\right)+20
Cancel out 20, the greatest common factor in 200 and 20.
68x-300=40+50x+20
Use the distributive property to multiply 10 by 4+5x.
68x-300=60+50x
Add 40 and 20 to get 60.
68x-300-50x=60
Subtract 50x from both sides.
18x-300=60
Combine 68x and -50x to get 18x.
18x=60+300
Add 300 to both sides.
18x=360
Add 60 and 300 to get 360.
x=\frac{360}{18}
Divide both sides by 18.
x=20
Divide 360 by 18 to get 20.
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}