Question 584080
Steve=s=? pounds
Mom=m=s+75 pounds
Steve+Mom=100

Equation:
Steve + mom = 100
s+s+75=100
2s+75=100
2s=100-75
2s=25
s=25/2
s=12.5

Together they weigh 100  
s+m=100
12.5+m=100
m=100-12.5
m=87.5 pounds


Answer: Steve weighs 12.5 pounds and mom weighs 87.5 pounds.