Question

The sum of liz's and melinda's ages is 28. if liz was 1/3 melinda's age 6 years ago, how old will liz be next year?

Answer 1

The first thing we must do for this case is to define variables:
We have then:
x: liz's age
y: melinda's age
We now write the system of equations:

`x + y = 28 x-6 = (1/3) (y-6)`
By solving the system graphically we have that the age of each one is currently:

`x = 10 y = 18`
Next year, the age of liz is:

`x + 1 = 10 + 1 = 11`
Answer:
Next year, Liz's age is 11 years.
Note: see attached image for the graphic solution.