Question 57050
6.  Taking into account just the intercepts to graph this line (though the slope is found the same way regardless of which two points you choose):
*[invoke find_equation_of_line 0, 3, 6, 0]

15. *[invoke find_equation_of_line 5, 3, -3, -4]

25. Forget the graph on this one.  Also note...4655 is the distance between base elevation and summit elevation.
*[invoke find_equation_of_line 0, 4655, 15840, 0]

50. 16 + 2x - 8y = 0 in slope-intercept form:
-8y=-2x-16
y=(1/4)x+2.  The slope is 1/4 and here is the graph:
*[invoke find_line_by_slope_and_point 0, 2, ".25"]
(Although I already worked out the equation, I did this mainly for the graph.)