How do you make 3x−9=7y in standard form

Any is very appreciated! (picture is provided below)not sure how to do this at all won't lie

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

The human resources manager at a company records the length, in hours, of one shift at work, x. he creates the probability distribution below. what is the probability that a worker chosen at random works at least 8 hours? probability distribution px(x) 6 hours 7 hours 8 hours 9 hours 10 hours 0.62 0.78 пол