Solve 8+9*9+r=

$$8 + 9 \cdot 9 + r =$$

Evaluate

$$r+89$$

Solution Steps

Multiply 9 and 9 to get 81.

$$8+81+r$$

Add 8 and 81 to get 89.

$$89+r$$

Differentiate w.r.t. r

$$1$$

Steps Using Derivative Rule for Sum

Multiply 9 and 9 to get 81.

$$\frac{\mathrm{d}}{\mathrm{d}r}(8+81+r)$$

Add 8 and 81 to get 89.

$$\frac{\mathrm{d}}{\mathrm{d}r}(89+r)$$

The derivative of a polynomial is the sum of the derivatives of its terms. The derivative of a constant term is 0. The derivative of ax^{n} is nax^{n-1}.

$$r^{1-1}$$

Subtract 1 from 1.

$$r^{0}$$

For any term t except 0, t^{0}=1.

$$1$$