# Expression input used in graph of the form g(x,y)

**URL:** <https://cl.desmos.com/t/expression-input-used-in-graph-of-the-form-g-x-y/321>\
**Category:** Questions\
**Tags:** sketch\
**Created:** [November 27, 2018, 1:04am UTC](https://cl.desmos.com/t/expression-input-used-in-graph-of-the-form-g-x-y/321 "2018-11-27T01:04:44Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Nicholas\_Koberstein](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/nicholas_koberstein/32/137_2.png) [@Nicholas\_Koberstein](https://cl.desmos.com/u/Nicholas_Koberstein)\
**Post date:** [November 27, 2018, 1:04am UTC](https://cl.desmos.com/t/expression-input-used-in-graph-of-the-form-g-x-y/321/1 "2018-11-27T01:04:44Z")

</div>

I’m working on a Desmos Activity that will accompany a lesson on slope fields.

Currently, I am able to display a slope field and have a moveable point for students try to follow the slopes. On the next slide, students can select coordinates and view particular solutions that involve that coordinate. I also have students sketch particular solutions.

What I’d like is to have slides that allow students to input their own DEs (in the form dy/dx = …) and have the graph display this. I’m not sure how to take the student input and replace the g(x,y) = part of my graph.

Here is my work so far: [Slope Fields • Activity by Nicholas Koberstein](https://teacher.desmos.com/activitybuilder/custom/5bfc81697f696774c69fe0d5)

THANKS!

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<div class="post-metadata">

**Author:** ![HumanizedMath](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/humanizedmath/32/2947_2.png) [@HumanizedMath](https://cl.desmos.com/u/HumanizedMath)\
**Post date:** [November 29, 2018, 4:58am UTC](https://cl.desmos.com/t/expression-input-used-in-graph-of-the-form-g-x-y/321/2 "2018-11-29T04:58:20Z")

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In the graph component define the function, in your case g. To connect it to a student input you can either use an expression

```auto
function("g"): simpleFunction(exp15.latex,"x","y")

```

or use a table and refer to the cell the student is supposed to type into.

```auto
function("g"): simpleFunction(table15.cellContent(1,1),"x","y") 

```

> **[Slope Fields with Student Input • Activity Builder by Desmos](https://teacher.desmos.com/activitybuilder/custom/5bff6c8e7259e06190d8bf01)**
>
> This activity displays several slope fields of differential equations and has students sketch particular solutions that include indicated coordinates.