3z + 6
3z and 6 has greatest common factor, that is 3. Divide 3z and 6 by the greatest common factor (3).
3z ÷ 3 = z
6 ÷ 3 = 2
So, we could work on the expression as following.
3z + 6
= 3 × z + 3 × 2
From the expression above, we should separate 3 from z and 2 by a parenthesis to make distributive property.
3 × z + 3 × 2
= 3(z + 2)
SUMMARY
3z + 6
= 3 × z + 3 × 2
= 3(z + 2)