Find the equation for k

Question

The sum of n and k is 16, and the product of n and k is 60, which equation must satisfy k

K^2-16k+60=0 K^2-10k+60=0 K^2-6k+60=0 K^2-60=0

Answer 1

n+k = 16

nk = 60

(

k = 60/n

n + 60/n = 16

n^2 + 60 = 16n

n^2 -16n + 60 = 0

(n-6)(n-10) = 0

n =6, 10

(n,k) = (6, 10) or (10, 6)

6 and 10 sum to 16

their product = 60

answer is either of the 1st two options, and not the last two