Question

if you were to graph x=5, how would it look like? And where can I find an online graphing calculator? and what does it mean in math for something to be undefined?

What exactly is x=5? is it a function or something?

Answer 1

x=5 is a vertical line, 5 units to the right of the y-axis

it is not a function, since it fails the "vertical line" test, that is , for a given x, there is more than one value of y.

Any relation, such as x + y = 8 merely describes the relationship between the x and y coordinates of a specific set of ordered pairs.
e.g. (1,7), (5,3) or (-2,10) all have the relationship that if you add them you get 8, that is, x + y = 8

so when you have x = 5, points such as (5,4), (5,1) or (5,-456) all satisfy the given relation.

for an online graphing calculator, do a google search, I actually had one this morning, but did not mark the page.

Answer 2

found the page

Here is a simple graphing program.

http://www.coolmath.com/graphit/

enter the function value without the y = part

e.g. for y = x^2 - 4
just enter x^2-4, then click on the "eval"

at the bottom you will see the coordinates of the cursor.

Answer 3

thank you!