how would you graph y=2x-3

Question

I need help with this problem, I have been stuck on it for about 2 hours

Answer 1

Hi Bob!

Your problem is in slope intercpet form. (y =xm + b) where m = the slope of the line and b = y-intercept.

There are a couple of ways to solve this problem, I'm going to show you the numeric way to solve the problem. create a graph o values for x and y. Plug in each value to get the value of y and create coordinate pairs to graph. You know that (0,-3) is a point since -3 is the y-intercept.

x    0     2     1

y    -3    1     0   

y = 2(2)-3

y = 4-3

y = 1

 

y=2(1)-3

y = 3-3

y = 0

So you have coordinate pairs of (0,-3), (2,1), (1,0). Plot the points and connect them with a ruler.

 

Hope this helps!

Answer 2

A much easier way to do it, if you prefer is to look at the graph and the problem. The problem say "2X-3", "-3" is your y-intercept. This means that you start at the origin and either go up or down the amount of the y-intercept. In this case you have "-3" so you go down three and start your graph at (0,-3). Now because there is a 2 in fron of X, you go over 2 and up 2. So that takes you to (2,1). 

Answer 3

To graph a line, the equation must be in slope-intercept form y=mx+b. The good thing is that it is in the correct form. First you look at "b" which is the y-intercept. It is a -3. This means that for your first point, you just go down 3 from the middle.

From that point, use the slope (m) to get your other point. If the slope (m) is 2, there is an understood (1) at the bottom. Now from that point, go up 2, and right 1. There is your second point. Connect the two dots and tail the line off in both directions, and you have your line.