Question

Factor the Algebraic expression 21a + 9​

Answer 1

3(7a+3)

Explanation:

Find the common factor

3 multiplied by 7 equals 21, and 3 times 3 equals 9

Take the common factor out of the parenthesis

3( _a+_)

and put in 7 and 3 in the appropriate spots

3(7a+3)

double check

3 times 7 is 21, 3 times 3 is 9

3(7a+3)= 21a+9

Answer 2

3(7a + 3)

Explanation:

3 is the greatest common factor between 21 and 9

put 3 outside the parenthesis and divide both numbers by 3

3(7a + 3)