How do you graph #y=4x-12# using intercepts?

1 Answer
Mar 2, 2017

Answer:

The intercepts are #(0,-12)# and #(3,0)#. The graph is a straight line through these two points.

Explanation:

An intercept is a point when a line crosses an axis. Mathematically, this is where one of the coordinates is equal to #0# - when it crosses the #y# axis the #x# coordinate is #0#, and when it crosses the #x# axis the #y# coordinate is #0#.

The #y# intercept is found by setting #x=0# in the equation, so

#y=4x-12#

#y=4xx0-12#

#y=-12#

so the #y# intercept is the point #(0,-12)#

The #x# intercept is found by setting #y=0# and solving, so

#0=4x-12#

#12=4x#

#12/4=3=x#

so the #x# intercept is at #(3,0)#

Now we have the two points on the graph #(0,-12)# and #(3,0)#.

Since it is a straight line graph, simply connect the dots and draw a long line.

It should look something like this

graph{4x-12 [-10, 10, -20, 20]}