2x^4-18x^2+5=0 needing to find the zero in polynomial form

Our goal is to collect email addresses from 60% of customers who purchase a product." so that means if i talk to 95 customers, i need to persuade to provide an email address?

Which expressions are equivalent to k/2 choose 2 answers: a k-2 b 2/k c 1/2k d k/2 e k+k

If f(x) = 4x - 3 and g(x) = x + 4, find (f - g) (x)