(5+3i)(2+4i)how do you solve in quadratic form

Brook states that the distance on the line is 4 units. caleb states that the whole line does not have a distance because it continues on forever. vivian states that the line is 6 units long. which distance did brook measure? which distance did vivian measure?

Given f(x)= 9x+1 and g(x)=x^3, choose the expression (f*g)(x)

Find the greatest common factor of the followig monomials 21u^5v,3u^4v^6, and 3u^2v^5