Hi! Super easy question, but how do you make a perimeter expression? ​

Triangle inequality theorem state if each set of three numbers can be the lengths of the sides of a triangle. 1. 9, 8, 22. 2. 5,10,12. 3. 7,10,22. 4. 4,11,12. 5. 11,9,10. 6. 10,4,19. 7. 3,12,10. 8. 4,3,2. 9. 6,5,13. 10. 7,12,20. me .

Two variables, x and y, vary inversely, and x=12 when y=4. what is the value of y when x=3?

How do i i solve this equation? -18 = x/3 + 3