Shiloh is 7 years older than courtney. shiloh's age is 13 years less than two times courtney's age. the system below models the relationship between shiloh's age (s) and courtney's age (c): s = c + 7 s = 2c − 13 which of the following methods is correct to find shiloh's and courtney's age?

I'm afraid I don't see the models you have written about although I do know the answer. (C= Courtney's age, S= Shilo's age)

Shilo is 7 years older then Courtney, which equals to C+7=S.

While at the same time Shilo is 13 years younger then twice Courtney's age. This turns into Cx2-13=S.

c+7=cx2-13. This is the equation, now lets work it out.

Add 13 on each side and you get

c+20=2c

Now we subtract c from each side and we get

20=c Therefor we have found out that Courtney is 20 years old.

Shilo being 7 years older then Courtney is 27