Write the point-slope form of the given line that passes through the points (0, 3) and (4, 0). identify (x1, y1) as the x-intercept of the line.

The x intercept is where the line crosses the x axis or where y=0
(x,0) is the x intercept
oh, look
(4,0)
the x intercept is x=4

anyway
point slope form
y-y1=m(x-x1)
for a line passing throuh (x1,y1) and slope is m

find slope

slope between (x1,y1) and (x2,y2) is
(y2-y1)/(x2-x1)
given
(0,3) and (4,0)
slope=(0-3)/(4-0)=-3/4

a point is (4,0)
y-0=-3/4(x-4)
y=-3/4(x-4)
xintercept is x=4