Solve 3(a + 3) – 6 = 21.

a=6

Step-by-step explanation:

to find the value of a you need to simplify the equation first. so...

3(a+3)-6=21 (you remove the bracket first)

3a+9-6=21

3a+3=21 (you collect the like terms then)

3a=21-3

3a=18 (then you both divide both sides by 3 to find the value of a)

a=18/3

a=6

to check your answer substitute 3 instead of a

3(a+3)-6=21

3(6+3)-6=21

3(9)-6=21 (according to BODMAS since multiplication comes first you multiply 3 with 9 before subtracting it from 6.)

29-6=21

21=21

4

step-by-step explanation:

a² + b²= c²

24² + 7² = c²

c= 25