Factor the expression. 49b^2 42b 9

a. (7b 3) 2

b. (-7b - 3) 2

c. (7b - 3) 2

d. (-7b 3) 2

If you would like to factor the expression 49b^2 + 42b + 9, you can do this using the following steps:

49b^2 + 42b + 9 = (7b + 3) * (7b + 3) = (7b + 3) ^2 = 7^2b^2 + 2 * 3 * 7b + 3^2 = 49b^2 + 42b + 9

The correct result would be a. (7b + 3) ^2.