Problema Solution
The sum of 4 times Lisa's age and 7 times john's age is 169. John is 1 year more than twice as old as Lisa. Find each of their ages.
Answer provided by our tutors
let
x = the age of Lisa
y = the age of John
sum of 4 times Lisa's age and 7 times john's age is 169
4x + 7y = 169
John is 1 year more than twice as old as Lisa
y = 1 + 2x
by solving the system of equations
4x + 7y = 169
y = 1 + 2x
we find
x = 9 years
y = 19 years
Lisa is 9 years old.
John is 19 years old.