Answer:
n = 4, m = 1
Step-by-step explanation:
Given the 2 equations
3m + n = 7 → (1)
m + 2n = 9 → (2)
Rearrange (2) expressing m in terms of n, by subtracting 2n from both sides
m = 9 - 2n → (3)
Substitute m = 9 - 2n into (1)
3(9 - 2n) + n = 7 ← distribute left side
27 - 6n + n = 7 ← simplify left side
27 - 5n = 7 ( subtract 27 from both sides )
- 5n = - 20 ( divide both sides by - 5 )
n = 4
Substitute n = 4 into (3) for corresponding value of m
m = 9 - (2 × 4) = 9 - 8 = 1
Thus m = 1 and n = 4
