Question

Lindsay is 5 55 years younger than Mark. Seven years ago, the sum of their ages was 31 3131. Let l ll be Lindsay's age and let m mm be Mark's age. Which system of equations represents this situation?

Answer 1

The system of equations that represents this situation is

M - L = 55

L + M = 45

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