Can someone help me with these 3 please?

Find the solution(s) to the system of equations. select all that apply y=x^2-1 y=2x-2

Ibeg you to me 20. a reaction produces 4.93 l of oxygen, but was supposed to produce 1 mol of oxygen. what is the percent yield?

Asandwich shop has 18 tables. each table seats up to 4 people. to find the greatest number of people that can be seated, you can solve p4 ≤ 18. which step is the best way to solve the inequality? plz asap i repeat plz