Guys algebra 2 i am really struggling

Rearrange the formula c^2 = a^2 + b^2 for b

Nell has a sales clerk job that pays $12 per hour for regular gas work hours. she gets double time for any hours over 40 that she works in a week. how many hours did nell work if her weekly pay was $744

If olu is twice as old as funmi if the sum of their ages is 60 how old is olu