Pass parameter to an equation

I start building this activity and would like to emphasis it (as explained in the screen). The first screen is problematic because the shoot might launch not from the gun position. Hence, I want the student to input ‘m’ only the ‘slop’. what I couldn’t figure out is how to incorporate the ‘m’ with the equation template that ensure the start position of the shoot ?

Pass the input ‘m’ slop to an equation

If my thinking is right, instead of using t in your definition of a, use t+L_x?

Hello,

Your answer is well noted. I’m aware of the ‘t’ issue and its relation with Lx and Px.
For now my focus and question is about constructing the “bullet line”. How to incorporate the ‘m’, input by the student, into a predefined paramtric equation like: (y - 1) = {m} ( x - 10) or
function: y = {m} x - 10 {m} + 1

Thanks
Itzik

בתאריך יום א׳, 7 בפבר׳ 2021, 19:35, מאת Daniel_Grubbs via Desmos Activity Builder Support ‏<desmos@discoursemail.com>:

Sorry misunderstood. Is this what you mean?

In graph CL:

number(`m`): when InputL3.submitted InputL3.numericValue
otherwise numericValue("1/0") #makes m undefined (and as a result, f(x)) if not submitted

In your graph:

f(x)=m(x-L_x)+L_y

Exactly what I was looking for. So simple and clean, excellent.

Thanks
Itzik

בתאריך יום ג׳, 9 בפבר׳ 2021, 7:55, מאת Daniel_Grubbs via Desmos Activity Builder Support ‏<desmos@discoursemail.com>: