I NEED THIS SOLVED ASAP 50 POINTS

1.) 2x + y = 3 2.) x - 2y = -1 if equation 1 is multiplied by 2 and then the equations are added, the result is a.3x = 2 b.3x = 5 c.5x = 5

Solve 3x-18=2y and 5x-6y=14 by elimination or substitution . show all !

Adam used 1072.4 gallons of water over the course of 7 days. how much water did adam use, on average, each day?