Here's how to solve this problem:
**1. Assign variables:**
* Let's use "t" to represent the cost of one taco.
* Let's use "d" to represent the cost of one drink.
**2. Set up equations:**
We can translate the given information into two equations:
* Equation 1: 5t + 3d = 60
* Equation 2: 3t + 2d = 40
**3. Solve for "d" (the cost of one drink):**
There are a couple of ways to solve this system of equations. Here's one method using elimination:
* **Multiply Equation 2 by -5:** -15t - 10d = -200
* **Multiply Equation 1 by 3:** 15t + 9d = 180
* **Add the two equations together:** -d = -20
* **Divide both sides by -1:** d = 20
**Answer:** One drink costs $20.
