4x - 5y = 15
put x=0, 4(0) - 5y = 15
-5y = 15
y = -3
coordinates (0,-3)
put y=0, 4x - 5(0) = 15
x = 15/4
coordinates (15/4,0)
put y=1, 4x - 5(1) =15
4x = 20
x = 5
coordinates (5,1)
Plot the three coordinates to obtain a straight line.
Note: You can also use other points rather from what i mentioned.
Hope it helped!
