Karen is seven years older than suzanne. four years ago, karen was twice as old as suzanne was. how are they now?

Karen age=k
suzanne age=s

karen (k) is (=) 7 years older (+7) than suzanne(s)
k=7+s

four year ago means
s-4 and k-4

four years ago (-4 to all) karen (k) was (=) twice (2 times) suzzane (s)
k-4=2(s-4)
distribute
k-4=2s-8
add 4 to both sides
k=2s-4
we know that k=7+s so subsitute 7+s for k
7+s=2s-4
add 4 to both sides
11+s=2s
subtract s from both sides
11=s

suzanne=11
subsitute 11 for s in k=s+7

k=7+11
k=18

karen=18
suzanne=11