Solve for x
x=7
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\frac{x-4}{\frac{80}{4}+\frac{1}{4}}=\frac{\left(\frac{2}{3}\right)^{2}}{1+2}
Convert 20 to fraction \frac{80}{4}.
\frac{x-4}{\frac{80+1}{4}}=\frac{\left(\frac{2}{3}\right)^{2}}{1+2}
Since \frac{80}{4} and \frac{1}{4} have the same denominator, add them by adding their numerators.
\frac{x-4}{\frac{81}{4}}=\frac{\left(\frac{2}{3}\right)^{2}}{1+2}
Add 80 and 1 to get 81.
\frac{x-4}{\frac{81}{4}}=\frac{\frac{4}{9}}{1+2}
Calculate \frac{2}{3} to the power of 2 and get \frac{4}{9}.
\frac{x-4}{\frac{81}{4}}=\frac{\frac{4}{9}}{3}
Add 1 and 2 to get 3.
\frac{x-4}{\frac{81}{4}}=\frac{4}{9\times 3}
Express \frac{\frac{4}{9}}{3} as a single fraction.
\frac{x-4}{\frac{81}{4}}=\frac{4}{27}
Multiply 9 and 3 to get 27.
\frac{x}{\frac{81}{4}}+\frac{-4}{\frac{81}{4}}=\frac{4}{27}
Divide each term of x-4 by \frac{81}{4} to get \frac{x}{\frac{81}{4}}+\frac{-4}{\frac{81}{4}}.
\frac{x}{\frac{81}{4}}-4\times \frac{4}{81}=\frac{4}{27}
Divide -4 by \frac{81}{4} by multiplying -4 by the reciprocal of \frac{81}{4}.
\frac{x}{\frac{81}{4}}+\frac{-4\times 4}{81}=\frac{4}{27}
Express -4\times \frac{4}{81} as a single fraction.
\frac{x}{\frac{81}{4}}+\frac{-16}{81}=\frac{4}{27}
Multiply -4 and 4 to get -16.
\frac{x}{\frac{81}{4}}-\frac{16}{81}=\frac{4}{27}
Fraction \frac{-16}{81} can be rewritten as -\frac{16}{81} by extracting the negative sign.
\frac{x}{\frac{81}{4}}=\frac{4}{27}+\frac{16}{81}
Add \frac{16}{81} to both sides.
\frac{x}{\frac{81}{4}}=\frac{12}{81}+\frac{16}{81}
Least common multiple of 27 and 81 is 81. Convert \frac{4}{27} and \frac{16}{81} to fractions with denominator 81.
\frac{x}{\frac{81}{4}}=\frac{12+16}{81}
Since \frac{12}{81} and \frac{16}{81} have the same denominator, add them by adding their numerators.
\frac{x}{\frac{81}{4}}=\frac{28}{81}
Add 12 and 16 to get 28.
x=\frac{28}{81}\times \frac{81}{4}
Multiply both sides by \frac{81}{4}.
x=\frac{28\times 81}{81\times 4}
Multiply \frac{28}{81} times \frac{81}{4} by multiplying numerator times numerator and denominator times denominator.
x=\frac{28}{4}
Cancel out 81 in both numerator and denominator.
x=7
Divide 28 by 4 to get 7.
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}