Answer:
The system of equations that represents this situation is
M - L = 55
L + M = 45
Step-by-step explanation:
Let age of Lindsay is = L
Age of mark = M
Given that
Lindsay is 55 years younger than Mark.
⇒ L = M - 55
⇒ M - L = 55 ------ (1)
Seven years ago, the sum of their ages was 31.
⇒ ( L - 7 ) + (M - 7) = 31
⇒ L + M = 45 ------- (2)
Therefore the system of equations that represents this situation is
M - L = 55
L + M = 45