Question

IMPORTANT HELP HURRY

Andrew is two years older than Beatrice, and Chris is three years younger than Beatrice. The product of Andrew's age and Chris' age is 66. How old is Beatrice? (1 point) Extra Content
HINT: Look at the Answers
A. A b2 − b − 72 = 0; 8 years old
B. B b2 − b − 72 = 0; 9 years old
C. C b2 − b − 72 = 0; 10 years’ old
D. D b2 − b − 72 = 0; 11 years’ old

Answer 1

Let Bea = x
Therefore Andrew = x + 2
Chris = x - 3

Andrew * Chris = 66
(x + 2)(x - 3) = 66 Remove the brackets.
x^2 + 2x - 3x - 6 = 66
x^2 - x - 6 = 66 Subtract 66 from both sides.
x^2 - x - 72 = 0
(x - 9)(x + 8) = 0
Find the possible values of Bea's age

x - 9 = 0
x = 9 That value works. She can be plus 9 years old.

x + 8 = 0
x = - 8. There's no way she can be - 8 years old

So Bea is 9.
9 <<<<<< Answer