Solve -7/5d+4/3d

$$\frac { - 7 } { 5 d } + \frac { 4 } { 3 d }$$

Evaluate

$$-\frac{1}{15d}$$

Short Solution Steps

To add or subtract expressions, expand them to make their denominators the same. Least common multiple of 5d and 3d is 15d. Multiply \frac{-7}{5d} times \frac{3}{3}. Multiply \frac{4}{3d} times \frac{5}{5}.

$$\frac{-7\times 3}{15d}+\frac{4\times 5}{15d}$$

Since \frac{-7\times 3}{15d} and \frac{4\times 5}{15d} have the same denominator, add them by adding their numerators.

$$\frac{-7\times 3+4\times 5}{15d}$$

Do the multiplications in -7\times 3+4\times 5.

$$\frac{-21+20}{15d}$$

Do the calculations in -21+20.

$$\frac{-1}{15d}$$

Differentiate w.r.t. d

$$\frac{1}{15d^{2}}$$