How do you graph #y + 4 = -2x# by plotting points?

1 Answer
Jun 6, 2017

With functions that have a degree of #1# and are not reciprocal, we can determine that the function is linear. Thus, we can just find the intercepts and connect them with a straight line.

In this case, the intercepts are: #(-2, 0)# and #(0, -4)#.

Explanation:

So, the best way to graph this relation is to find the intercepts and connect them with a straight line.

I know this is a linear equation because the highest degree is #1#. The variables are not in the reciprocal format as well.

Anyways, let's first make an equation for the variables.

We'll start with #x# first.

#y+4=-2x#

#(y+4)/-2=x#

Now let's find the #x#-intercept by subbing in #y=0#.

#(y+4)/-2=x#

#(0+4)/-2=x#

#4/-2=x#

#-2=x#

Thus, the #x#-intercept is #(-2, 0)#.

Now let's make an equation for the #y#.

#y+4=-2x#

#y=-2x-4#

Now let's find the #y#-intercept by subbing in #x=0#.

#y=-2x-4#

#y=-2(0)-4#

#y=-4#

Thus, the #y#-intercept is #(0, -4)#.

All we have to do is connect them with a straight line and we have our graph.

graph{y+4=-2x [-10, 10, -5, 5]}

Hope this helps :)