Suppose two brown haired parents have a red haired child what are the genotypes of each parent

1) B - brown; b - red hair

Having brown hair is a dominant trait while red hair is recessive.

If the parents had a red-haired child it means they were carriers of the red hair trait, so their genotype is Bb

(they are heterozygotic)

The answer would be that they both are heterozygous.