Question 112132
Let x=Greg's present age
Then x-9=Rolly's presentage
In 7 years, Greg's age will be x+7
In 7 years, Rolly's age will be (x-9)+7 or x-2

Now we are told that:

(x-2)=1/2(x+7)+2  multiply each term by 2

2(x-2)=(x+7)+4  get rid of parens (distributive law)

2x-4=x+7+4 subtract x from and add 4 to both sides

2x-4+4-x=x-x+7+4+4  collect like terms

x=15-------------------------Greg's present age

x-9=15-9=6-----------------------Rolly's present age

CK

6+7=1/2(15+7)+2
13=11+2
13=13


Hope this helps---ptaylor