t2 sec 3 #17

To get this one, you need to remember that corresponding coefficients of equivalent polynomials are equal. In other words, if is equivalent to then you know that a = m, b = n, and c = p.

To solve this question, then, all we need to do is simplify the left hand side.

   

From that, we know that a = 6, b = 19, and c = 15. The question only asks us for b, so the answer is 19.