Question

In how many ways can a student choose a program of 5 courses if 9 courses are available, and two specific courses are required?
(combinations)
(Answer with step and reason, plz) ​

Answer 1

9_c_5+2

=9_c_7

=9*8*7*6*5*4*3*2*1/7*6*5*4*3*2*1

=9*8

=72

or

9_c_2

9*8/2*1

=9*4

=36