SOLUTION: Lisa is eight years older than Megan and Alyssa is two years younger than Megan. The sum of their ages is 42. How old is each girl ??

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Question 1065909: Lisa is eight years older than Megan and Alyssa is two years younger than Megan. The sum of their ages is 42. How old is each girl ??
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Write an equation for each statement
:
Lisa is eight years older than Megan
L = m + 8
and Alyssa is two years younger than Megan.
a = m - 2
The sum of their ages is 42.
L + m + a = 42
Replace L with (m+8); replace a with (m-2)
(m+8) + m + (m-2) = 42
m + m + m + 8 - 2 = 42
3m + 6 = 42
3m = 42 - 6
3m = 36
m = 36/3
m = 12 yrs is Megan's age
then
L = 12 + 8
L = 20 yrs is Lisa's age
and
a = 12 - 2
a = 10 yrs is Alyssa's age
:
:
Check
20 + 12 + 10 = 42