Help me out :)) 2(5x-1)+3x

Element x decays radioactively with a half life of 8 minutes. if there are 450 grams of element x, how long, to the nearest tenth of a minute, would it take the element to decay to 37 grams?

Given the following linear function sketch the graph of the function and find the domain and range. ƒ(x) = -5x + 4

If 3 3/4 lb. of candy costs 20.25 how much would 1lb. of candy cost