In humans, a gene (called COL1A1) codes for a certain collagen protein found in bone. The normal allele is denoted S, while the recessive allele s is associated with increased risk of fractures in both Ss and ss women. A recent study of 1,778 women showed that 1,194 were SS, 526 were Ss and 58 were ss.
Are these alleles in H-W equilibrium?
How do you know?

Yes alleles are in H-W equilibrium as their sum is equal to one

Explanation:

Given

Normal allele is "S" and is dominant over "s" which is a recessive allele

We will determine the genotype frequencies of the given population

The sum of above frequencies must be equal to one so that they satisfy the second equilibrium equation of  in Hardy Weinberg

Substituting the values in above equation, we get

Now we will find the allele frequencies

As per first equilibrium equation, sum of allele frequency must be equal to one

Hence, it satisfies the HW equilibrium equations.