Can someone pls help I can do this

Solve 2x+y=3 x+y=5 in substitution method

Solve 3x-18=2y and 5x-6y=6 by elimination show work

The boiling point of water at an elevation of 0 feet is 212 degrees fahrenheit (°f). for every 1,000 feet of increase in elevation, the boiling point of water decreases by about 2°f. which of the following represents this relationship if b is the boiling point of water at an elevation of e thousand feet? a) e = 2b - 212 b) b = 2e - 212 c) e = -2b + 212 d) b = -2e + 212