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Setting up and solving linear equations

Question: Michelle is 2 years younger than Angela. If the sum of their ages is 64 work out Michelle's age.

Question requires me to write the linear equation out and then solve it. But for the life of me I can't figure out how to do.

All I get is

M-2=A
M+A=64

Please help
Reply 1
Original post by Chrollo-Lucilfer
Question: Michelle is 2 years younger than Angela. If the sum of their ages is 64 work out Michelle's age.

Question requires me to write the linear equation out and then solve it. But for the life of me I can't figure out how to do.

All I get is

M-2=A
M+A=64

Please help


You have M-A=2 and M+A=64
Add the 2 equations together.
As below it should actually be M=A-2. Then proceed from there.
(edited 7 years ago)
The equations you start with aren't right, it should be:
M=A2 M = A - 2 as in, Michelle is Angela's age minus 2 and
M+A=64 M + A = 64

Simultaneous equations like this can either be solved by Elimination or Substitution, but I think the easiest would be substitution. This means that you can replace the second equation with (A2)+A=64 (A - 2) + A = 64 since you know M=A2 M = A - 2 . Then you solve for A. Once you know A, you can solve M by substituting A in the first equation.
Original post by Chrollo-Lucilfer
x


M + 2 = A
M + A = 64

M - A = -2
M + A = 64

.... Solve!

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