1. **State the problem:** We need to find the price of each regular pizza ($r$) and each deluxe pizza ($d$) given two orders.
2. **Set up the system of equations:**
- Brendan's order: $10r + 2d = 120$
- Eliana's order: $7r + 2d = 96$
3. **Use elimination to solve:**
Subtract the second equation from the first to eliminate $d$:
$$\cancel{10r} + 2d = 120$$
$$-\cancel{7r} - 2d = -96$$
-------------------
$$3r + 0 = 24$$
4. **Solve for $r$:**
$$3r = 24$$
$$r = \frac{24}{3} = 8$$
5. **Substitute $r=8$ into one original equation to find $d$:**
Using $7r + 2d = 96$:
$$7(8) + 2d = 96$$
$$56 + 2d = 96$$
$$2d = 96 - 56 = 40$$
$$d = \frac{40}{2} = 20$$
6. **Final answer:**
Each regular pizza costs $8$, and each deluxe pizza costs $20$.
Pizza Prices 00895A
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