Question: User: $-2r=16$
1. **State the problem:** Solve the equation $-2r=16$ for $r$.
2. **Formula and rules:** To solve for $r$, divide both sides of the equation by the coefficient of $r$, which is $-2$.
3. **Intermediate work:**
$$-2r=16$$
Divide both sides by $-2$:
$$\frac{-2r}{\cancel{-2}}=\frac{16}{\cancel{-2}}$$
4. **Simplify:**
$$r=-8$$
5. **Explanation:** Dividing both sides by $-2$ isolates $r$ on the left side. The division cancels the $-2$ coefficient, leaving $r$ alone. On the right side, $16$ divided by $-2$ equals $-8$. Thus, the solution is $r=-8$.