Find the value of k if (frac{5 + 2r}{(r + 1)(r – 2)}) expressed in partial fraction is (frac{k}{r – 2}) + (frac{L}{r + 1}) where K and L are constants

A.
3 
B.
2 
C.
1 
D.
1
Correct Answer: Option A
Explanation
5 + 2r = k(r + 1) + L(r – 2)
but r – 2 = 0 and r = 2
9 = 3k
k = 3