Answer:
The equation of a straight line is usually written in the
form :
y = mx + c, where the number c gives the values of the ycoordinate
where the line crosses the yaxis and the number m is the
gradient or slope of the line.
Slope
of the line m at one point P1 = (x1, y1) through which the
line passes, can be calculatoed by equation (y  y1 ) / (x
 x1) = m
