What do the terms in the hardy-weinberg equations (p + q = 1 and p2 + 2pq + q2 = 1) represent?

P represents the frequency of the dominant allele (in decimal form) of a gene

q represents the frequency of the recessive allele (in decimal form) of a gene

These 2 alleles are different; one is dominant, one is recessive.

p^2 = the frequency of homozygous dominant individuals in the population (decimal form)

2pq = the frequency of heterozygous individuals in the population (decimal form)

q^2 = the frequency of homozygous recessive in the population (decimal form)