Twice a certain number is subtracted from 9 times the number. The result is 21. Find the number.​

According to statistics a person will devote 32 years to sleeping and watching tv. the number of years sleeping will exceed the number of years watching tv by 18. over a lifetime, how many years will the person spend on each of these activities

If c(x) = 4x – 2 and d(x) = x2 + 5x, what is (cxd)(x)

Miguel’s teacher asks him to color 4/8 of his grid. he must use 3 colors: red, blue, and green. there must be more green sections than red sections. how can miguel color all the sections of his grid to follow all the rules