Answer:
22
Sarah's age is best represented by M-24 or as the question used x-24 where the mother's age is best represented by M where the question used x.
Explanation:
We are given that Sarah (S) is 24 years younger than her mother (M).
So S=M-24.
We are given that Sarah (S) and her mom's age adds up to 68.
So S+M=68.
We are going to solve this system by substitution since one of the variables is solved for. I'm going to plug first equation into second like so:
(M-24)+M=68 I replaced S with M-24.
M+M-24=68 Put like terms together.
2M-24 =68 Combined the like terms.
2M = 92 Added 24 on both sides.
M = 92/2 Divided 2 on both sides.
M = 46 Simplified the 92/2.
So her mother's age is 46.
We know that S=M-24 so S=46-24=22.
Sarah is 22 years old.