Final answer:
Daley made an error in his solution in step 2. The correct equivalent equation is b = 7 - 1.5s.
Step-by-step explanation:
Daley made an error in step 2 of his solution. In step 2, he divided both sides of the equation by 1.5 instead of multiplying. To solve for b, he should have multiplied both sides by 2, since 1.5 is the coefficient of b in the equation. The correct step 2 should be: 2(1.5b) = 2(10.5 - 2.25s), which simplifies to 3b = 21 - 4.5s. So, the correct equivalent equation is b = 7 - 1.5s.