1. **Problem 27:** Given the system of equations: $$2a - c = 0$$ $$3a + 2 = 2c$$ Phil found $a = 2$. We need to find $c$. 2. **Step 1:** Substitute $a = 2$ into the first equation: $$2(2) - c = 0$$ $$4 - c = 0$$ 3. **Step 2:** Solve for $c$: $$c = 4$$ 4. **Step 3:** Verify by substituting $a = 2$ and $c = 4$ into the second equation: $$3(2) + 2 = 2(4)$$ $$6 + 2 = 8$$ $$8 = 8$$ This confirms $c = 4$ is correct. --- 5. **Problem 28:** Cheri charges $19 for a small lawn and $29 for a large lawn. She cut 13 lawns and earned $287. 6. **Step 1:** Define variables: $s$ = number of small lawns $l$ = number of large lawns 7. **Step 2:** Write the system of equations based on the problem: Number of lawns: $$s + l = 13$$ Total earnings: $$19s + 29l = 287$$ 8. **Step 3:** Match with the given options. The correct system is option (a): $$s + l = 13$$ $$19s + 29l = 287$$