I need some assistance on a question could someone please help?
Here is the question in the book.
Do the points (3, -4) (18, 6) and (9, 0) all lie on the same line? If so what is the equation of the line.
I looked in the answer section the answer is yes and the equation is 2x-3y=18
I do not know how to work the three points into the equation and I can't find any solutions in the book to help me.
Thank's for the help.
Mark

Easiest way is to draw a graph :p

How do you mean worked out form? What do you disagree with in my answer? It would be nice if you had replied to help me help you, rather than just giving negative rep.

The best way to do it that I can see is to graph it, and if you can put a line through all 3, then work out m and c in y = mx + c by finding the y intercept and gradient of the line you have drawn.

Since the topic is "graphing linear function", I assume you want to graph it.

Well, let's do this by substituting the x and y values in the equation (left handside of equation) to see if we will get 18 (right handside of the equation).
1. x = 3; y = -4 gives 2(3) - 3(-4) = 6 + 12 = 18

2. x = 18; y = 6 gives 2(18) - 3(6) = 36 - 18 = 18

3. x = 9; y = 0 gives 2(9) - 3(0) = 18 - 0 = 18

Hope this helps