In five years, josh will be 21 years old. how old is he now? let j represent josh's current age. which formula would correctly calculate josh's current age?

Barbara deposited $300 in the bank. if the bank pays her simple interest at the rate of 4 percent per year, how much money will she have in her account at the end of 9 months?

For f(x) = 3x+1 and g(x) = x2 - 6, find (g/f)(x)

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?