Answer:
1 = brother's age now.
4 = brothers age in 3 years.
7 = girls age now.
10 = girls age in 3 years.
Step-by-step explanation:
You want to get x by itself first.
(x + 6) + 3 = 2(x + 3) + 2
x +9 = 2x + 8
-x + 9 = 8
-x = -1
x = 1
This is her brothers age when she is 6 years older than him.
Now you will take the 1 and put it in the x +3 = brother's age in 3 years.
The brother will be 4 in 3 years.
The girl will be 7 when her brother is born.
Then you will take the 1 and put it into (x + 6) +3 = 10.
The girl will be 10 in 3 years.
1 = brother's age now.
4 = brothers age in 3 years.
7 = girls age now.
10 = girls age in 3 years.