How do you graph #y=1/4x-3# by plotting points?

1 Answer
May 13, 2018

See below.

Explanation:

#y = 1/4x-3#

We know that the equation of a straight line with slope #(m)# and #y-#intercept #(c)# is: #y=mx+c#

Hence, in this example we have a linear function #(y)# with slope #1/4# and #y-# intercept #-3#

To graph a straight line by plotting points only requires two distinct points.

Since the #y-#intercept is #-3# we already know that the point #(0, -3)# is on the line.

Now let's find the #x-#intercept, where #y=0#

#0=1/4x-3#

#1/4x = 3#

#x=12 -> (12,0)# is on the line.

Now we can plot the two points: #(0,-3) and (12,0)# and draw a straight line between them and extending indefinitely in both directions, as shown below.

graph{(y-(x/4-3))(x^2+(y+3)^2-0.1)((x-12)^2+y^2-0.1)=0 [-11.35, 20.67, -7.3, 8.72]}