Question

P (purple) and p (white) are the dominant and recessive alleles for flower color in peas. Similarly, A (axial) and a (terminal) are the dominant and recessive alleles for flower position in peas. Two plants with the genotype PpAa are crossed. Which genotype is indicative of white axial flowers?

Answer 1

You know that it is white and white is recessive - so both alleles for color will be recessive. Two possible combinations will give an axial flower and you don't know which one it is based on the info given.