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:
[tex]x + y = 28
x-6 = (1/3) (y-6)[/tex]
By solving the system graphically we have that the age of each one is currently:
[tex] x = 10
y = 18[/tex]
Next year, the age of liz is:
[tex]x + 1 = 10 + 1 = 11
[/tex]
Answer:
Next year, Liz's age is 11 years.
Note: see attached image for the graphic solution.
