What is the slope and intercept for #y=1/2x-3# and how would you graph it?

1 Answer
Oct 10, 2015

slope = 1/2, y-int = -3.

Explanation:

We know that straight lines use equation:

#y = mx + b#
where m is the slope and b is the y-intercept.

If y is by itself on one side of the equals sign, then slope is always the number in front of x, and the y-intecept is always the number by itself (without an x)

In this case:
#m= 1/2# (slope)

and

#b = -3# (y-intercept)

The graph looks like this:
graph{y=.5x-3 [-10, 10, -5, 5]}

How do you make the graph? Pick an x value, plug into the equation, and then see what y you get. Put that (x,y) point on the graph. Do this for a few points and then connect the dots.

ex:

  • x=0
    #y = (1/2 \times 0 ) -3#
    #y = -3#
    #(x,y) = (0, -3)#

  • x=1
    #y = (1/2 \times 1 ) -3#
    #y = 1/2 -3#
    #y = -2.5#
    #(x,y) =(1, - 2.5)#

  • x=6
    #y = (1/2 \times 6 ) -3#
    #y = 3 -3#
    #y = 0#
    #(x,y) =(6, 0)#