(1,0),(0,4)
slope = (4 - 0) / (0 - 1) = -4/1 = -4
the y int is when x = 0.....so ur point (0,4) tells us that the y int is 4
in y = mx + b form, the slope will be in the m position and the y int will be in the b position
y = mx + b
slope(m) = -4
y int (b) = 4
sub
y = -4x + 4 <== or 4x + y = 4....depending on what form u need it in