Solve 7(x-7.8)=2.1

$$7 ( x - 7.8 ) = 2.1$$

Solve for x

$$x=8.1$$

Steps for Solving Linear Equation

Divide both sides by 7.

$$x-7.8=\frac{2.1}{7}$$

Expand \frac{2.1}{7} by multiplying both numerator and the denominator by 10.

$$x-7.8=\frac{21}{70}$$

Reduce the fraction \frac{21}{70} to lowest terms by extracting and canceling out 7.

$$x-7.8=\frac{3}{10}$$

Add 7.8 to both sides.

$$x=\frac{3}{10}+7.8$$

Convert decimal number 7.8 to fraction \frac{78}{10}. Reduce the fraction \frac{78}{10} to lowest terms by extracting and canceling out 2.

$$x=\frac{3}{10}+\frac{39}{5}$$

Least common multiple of 10 and 5 is 10. Convert \frac{3}{10} and \frac{39}{5} to fractions with denominator 10.

$$x=\frac{3}{10}+\frac{78}{10}$$

Since \frac{3}{10} and \frac{78}{10} have the same denominator, add them by adding their numerators.

$$x=\frac{3+78}{10}$$

Add 3 and 78 to get 81.

$$x=\frac{81}{10}$$