Question

Amy is 9 years older than her brother john. their combined age is 23. write an expression to represent johns age (use x)

Answer 1

Let x the age of John
Amy's age = x + 9
from question, we get,
John's age + Amy's age = 23
x+(x+9)= 23
=> x + x + 9 = 23
=> 2x = 23 - 9
=> x = 14/2
=> x = 7