Tom is 4 more than twice Andrews age. Sara is 8 less than 5 times Andrews age. If Tom and Sara are twins, how old is Andrew? Show your work

T = 4 + 2A

S = 5A - 8

T = S

Since T and S are equal, set them against each other

2A + 4 = 5A - 8

Subtract 2A from each side, and add 8 to each side

12 = 3A

Divide each side by 3

A = 4

So Andrew is 4 years old

If Andrew is 4, then Tom is twice that plus 4, or 12. Sarah is 5 times 4 less 8, or 12.