Answer:
Solve the given system first
Find b:
Find a:
- a - (-2) = 7
- a = 7 - 1
- a = 5
Verify the options for correctness:
- 2a + b = 2(5) + (-2) = 10 - 2 = 8, correct
- 2a - 2b = 2(5) - 2(-2) = 10 + 4 = 14, incorrect
- a - 2b = 5 - 2(-2) = 5 + 4 = 9, incorrect
- 2(a - b) = 2(5 - (-2)) = 2(7) = 14, incorrect