How do you graph #y=7/2x-2#?

1 Answer
Apr 3, 2018

See procedure below.

Explanation:

The following procedure will give you the coordinates of 2 data points. As we work them out, put them on your graph paper. Then you can draw a line between them and extend them as far as you like.

Plug in 0 for y and find the value of x that satisfies the equation:

#y = 7/2x - 2#

If #y = 0#, then #0 = 7/2x - 2#

Now, solve for x.
Add 2 to both sides. Then we have #2 = 7/2*x#
Multiply both sides by #2/7#.
So #2/7*2 = 2/7*7/2*x#
Cancel where possible. #2/7*2 = cancel(2)/cancel(7)*cancel(7)/cancel(2)*x#

So we have
#x = 4/7#
Therefore, you can plot a data point at #(4/7,0)#

Repeat, except plug in 0 for x. Starting with:

#y = 7/2x - 2#

If #x = 0#, then #y = 7/2*0 - 2#

That simplifies to #y = - 2#

Therefore you can plot a second point at #(0,-2)#. Those are the 2 points that cross the x-y axes. Draw the line.

I hope this helps,
Steve