Urgent Algebra Age Question

Question

Abigail will not reveal her age but says she is 3 years younger than his sister Kate. Ninety years ago, Kate was twice as old. How old is each now?

Answer 1

A=K-3

K-90=2(A-90)

K-90=2A-180

Substitute

K-90=2K-6-180

Can you take it from here and prove your answer?

Answer 2

A = K-3

2(A-90)= K-90

2A - 180 = K-90

2A = K -90 + 180 = K+90

2A = K+90

2A = 2K-6

subtract to get

0 = K -96

K = 96 years old for sister Kate now

A = 96-3 = 93 years old for Abigail now

90 years ago they were 6 and 3

6 is twice 3