Answer:
B
Step-by-step explanation:
Given the 2 equations
a - b + c = 3 → (1)
a + b + c = 7 → (2)
Subtract (1) from (2) term by term to eliminate a and c
a - a + b - (- b) + c - c = 7 - 3 , that is
0 + b + b + 0 = 4
2b = 4 ( divide both sides by 2 )
b = 2 → B
