Solve:

9 (30 + a) = 99

a =

9 (30 + a) = 99

270 + 9a = 99

- 99 - 99

171=9a

_ _

9 9

19 = a

Hello,

Example,

2 (x+3) = 12x

We divide with 2 at everywhere.

2 (x+3) / 2=12x/2

x+3=6x

Now x, be - x.

3=6x-x

3=5x

Wè divide with 5.

3/5=5x/5

3/5=x

Answer the questions.

9 (30+a) = 99

We divide with 9.

9 (30+a) / 9=99/9

30+a=11

Now 30, be - 30.

a=11-30

a = (-19)

#Tr

Good lessons!