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3 years ago

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?

Mathematics

1 answer:

Mrrafil [7]3 years ago

3 0

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.

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