ben's age in x yeears=30+x
daniel's age in x years is 2+x
when will ben's age in x years be 3 times of daniel's age in x years
30+x=3(2+x)
30+x=6+3x
minus x both sides
30=6+2x
minus 6 both sides
24=2x
divide by 2 both sides
12=x
answer is in 12 years