Question

Factor: (a+3)^2 -a(a+3)

Answer 1

3(a+3)

Explanation:

Expand the first set of brackets first

(a+3)^2

A^2 + 3a + 3a +9

=A^2 + 6a + 9

Expand the second set of brackets

-a(a+3)

=-a^2 - 3a

Add both sets together

3a + 9

Factorise:

3(a+3)

Answer 2

3(a +3)

Explanation:

(a+3)^2 -a(a+3)

FOIL

a^2 +3a+3a+9 -a(a+3)

Distribute

a^2 +3a +3a +9 -a^2 -3a

Combine like terms

3a +9

FACTOR out a+3

(a+3)( a+3 -a)

(a+3) (3)

3(a+3)