Which is equivalent to (2-5i)(-2+5i)

Solve for x i'll try to attach the files bc it's not letting me for some reason

Assume that a population of 50 individuals has the following numbers of genotypes for a gene with two alleles, b and b: bb = 30, bb = 10, and bb = 10. calculate the frequencies of the two alleles in the population’s gene pool.

What is the solution to the equation? k/6.4=8.7 2.3 5.568 15.1 55.68