Addition and subtraction and expression

Use the elimination method to find the solution to the system of equations. 2x - 3y = -9 -x + 3y = 6

Abby is preparing fruit punch for her party. she starts with a bowl filled with liquid that has 1/2 fruit juice and 1/2 sprite, but she decides it's too fruity. so she pours out 1/4 of the liquid, and then fills the bowl up again with sprite. what fraction of the punch is now sprite?

Can someone me with the property questions for 12 13 and 14 plz