Solve (2,9+81/2):x=21-15

$$( 2,9 + 8 \frac { 1 } { 2 } ) : x = 21 - 15$$

Solve for x

$$x=1,9$$

Steps for Solving Linear Equation

Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.

$$2,9+\frac{8\times 2+1}{2}=x\times 21+x\left(-15\right)$$

Multiply 8 and 2 to get 16.

$$2,9+\frac{16+1}{2}=x\times 21+x\left(-15\right)$$

Add 16 and 1 to get 17.

$$2,9+\frac{17}{2}=x\times 21+x\left(-15\right)$$

Convert decimal number 2,9 to fraction \frac{29}{10}.

$$\frac{29}{10}+\frac{17}{2}=x\times 21+x\left(-15\right)$$

Least common multiple of 10 and 2 is 10. Convert \frac{29}{10} and \frac{17}{2} to fractions with denominator 10.

$$\frac{29}{10}+\frac{85}{10}=x\times 21+x\left(-15\right)$$

Since \frac{29}{10} and \frac{85}{10} have the same denominator, add them by adding their numerators.

$$\frac{29+85}{10}=x\times 21+x\left(-15\right)$$

Add 29 and 85 to get 114.

$$\frac{114}{10}=x\times 21+x\left(-15\right)$$

Reduce the fraction \frac{114}{10} to lowest terms by extracting and canceling out 2.

$$\frac{57}{5}=x\times 21+x\left(-15\right)$$

Combine x\times 21 and x\left(-15\right) to get 6x.

$$\frac{57}{5}=6x$$

Swap sides so that all variable terms are on the left hand side.

$$6x=\frac{57}{5}$$

Divide both sides by 6.

$$x=\frac{\frac{57}{5}}{6}$$

Express \frac{\frac{57}{5}}{6} as a single fraction.

$$x=\frac{57}{5\times 6}$$

Multiply 5 and 6 to get 30.

$$x=\frac{57}{30}$$

Reduce the fraction \frac{57}{30} to lowest terms by extracting and canceling out 3.

$$x=\frac{19}{10}$$