d is being multiplied by 5.
You want d alone. The opposite operation to multiplication is division.
We must do the same operation to both sides of an equation.
We must divide both sides by 5.
![5d = 17.1](https://img.qammunity.org/2019/formulas/mathematics/college/oodhnoj09e1g1hplhg26evop1ce6nsxhjj.png)
![(5d)/(5) = (17.1)/(5)](https://img.qammunity.org/2019/formulas/mathematics/college/icqpjqt6hofyz8w61dmax3q1ewndi7x816.png)
Use a calculator to divide 17.1 by 5. You should get 3.42.
![d = 3.42](https://img.qammunity.org/2019/formulas/mathematics/college/4gwl2ztq2v32zsl642yfwfz9j16j6gge1h.png)