Answer:
[tex]3(5+7)[/tex]
Step-by-step explanation:
We are asked to factor out the given expression using distributive property.
First of all, we will find greatest common factor of 15 and 21.
Factors of 15: 1, 3, 5, 15
Factors of 21: 1, 3, 7, 21.
We can see that greatest common factor of 15 and 21 is 3.
[tex]15+21[/tex]
[tex]3\cdot 5+3\cdot 7[/tex]
Factor out 3:
[tex]3(5+7)[/tex]
Therefore, the factored form of our given expression would be [tex]3(5+7)[/tex].
