Juan wants to find two numbers such that their sum is 33 and their difference is 13.

In a singing competition, there are 150 participants. at the end of each round, 40% of the participants are eliminated. how many participants are left after n rounds?

This question is hard for me to answer can you me. the question is find the value of x.

Find the input (x) of the function y=-4/3x+20 if the output (y) is -80