Expert: Richard J. Raridon - 3/6/2009

Question
Line M is the slope but what is Line N?
The problem says to form the equations of both lines, what are the co-ordinates of the intersctions of lines M and N, co-ordinates of the intersections of lines M and N with the x-axis and co-ordinates of the intersection of lines M and N with the y axis.   The points for line M (1,3), (2,5), (8,17), there are more but I will try to figure them out after I figure out what I am supposed to be doing.
The points for line N (1,-1), (2,-3), (8, -15)
I am 47 years old and I just recently enrolled in an online program to further my career.  Algebra is required and I haven't had an algebra class in many many many years.

Answer
It only takes two points to determine a straight line.  
One form of the equation for a straight line is y = mx+b
so if you put in two points for line M you get 3 = m(1)+b and
5 = m(2)+b.  Then you have two equations and you can solve to get
m = 2 and b = 1.  Therefore, the equation for line M is y = 2x+1.  
Do the same thing for line N (you try it) and you get y = -2x+1.  
To find the intersection of M and N you simply take the two equations and solve for x and y.  You will find they cross at (0,1)
Good luck with your class.