Solve the simultaneous equations:

3a+2b=7

a-2b=5

a = 3, b = - 1

Step-by-step explanation:

Given the 2 equations

3a + 2b = 7 → (1)

a - 2b = 5 → (2)

Rearrange (2) expressing 2b in terms of a

2b = a - 5 ← Substitute into (1)

3a + a - 5 = 7

4a - 5 = 7 (add 5 to both sides)

4a = 12 (divide both sides by 4)

a = 3

Substitute a = 3 into (1) or (2) for corresponding value of b

Using (1)

9 + 2b = 7 (subtract 9 from both sides)

2b = - 2 (divide both sides by 2)

b = - 1