TI-Basic: How do you get an equation as an input?

I was playing around with programming on my TI-84 in math class today and I decide to try to write a program that reads an equation and than does a few things with it. But I'm having trouble reading an equation. I tried :Prompt Y1 but I kept getting a data type error when I try to use the program. Does anyone have any ideas on how to accomplish this? Thanks in advance.

Solution

I'm not sure if the TI-84 is the same, but on the 83 this will work if you put the equation in quotes when you enter it. So for example, using the following program:

PROGRAM:TEST
:Prompt Y1
:ClrDraw
:DispGraph

Running it:

prgmTEST
Y1=?"2X+1"

Will cause the graph for y=2x+1 to be drawn (and any other equations you already had entered at the time, IIRC).