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]}