Answer:robert=120lbs,genesis=100
Step-by-step explanation:take genesis as (x) and since robert is 20 pounds heavier he would be (X+20) so:
x+(x+20) =220lbs
2x+20=220
2x=220-20
2x=200
x=100 which we took as genesis
which leaves robert's weight 100 +20 =120