Question

d) Harriet is x years old. Martha is 5 years younger than Harriet. The product of their ages is 84. How old are Harriet and Martha?​

Answer 1

Harriet is 12; Martha is 7.

Explanation:

Harriet's age = x

Martha's age = x - 5

product of ages = x(x - 5)

product of ages = 84

x(x - 5) = 84

x² - 5x - 84 = 0

(x - 12)(x + 7) = 0

x - 12 = 0 or x + 7 = 0

x = 12 or x = -7

Since a negative age is not allowed, x = 12.

Answer: Harriet is 12; Martha is 7.