Colour and Correctness

I’d like to do a couple of things here.

First, is it possible that when the student enters their equation, that the line they generate is the same colour as the line in the graph? How do I do that?

Also, I’d like there to be a check or cross in each of the math input boxes, but I can’t seem to make it work. If I enter the correct equation, it comes up as incorrect in the box.

And lastly, at the moment, a student has to enter all four equations before they can submit. Can their answer be checked automatically after each equation? Maybe without having a submit button?

Many thanks


If you set up some default functions for g(x), f(x) etc. in the graph and make them invisible, you are able to set up four new lines using y=g(x), y=f(x) etc. which you can assign colours to because they will be valid functions. Once you’re in the activity, the functions will be overwritten in the CL and you won’t see the graphs until a function is entered.


The LaTeX you’re comparing to is not correct, which is why it’s marking as incorrect even if you put in the correct equation. Your best bet is to copy the function directly from the graph, and paste it into your CL, and it will format the LaTeX correctly - for example,
y=\frac{2}{3}x+5\ \left\{-3<x<2\right\}
rather than y=2/3x+5 {-3<x<2}

Check Automatically

If you remove the eqn12a.submitted etc. then it will mark the answer immediately (also while the student is typing!). If this is not what you want, then it may be best to force a submit button on each entry by using showSubmitButton: true

All of the above tweaks should combine to give you what you’re after:

First of all, can I give you my sincere apologies for not having replied to you before now. Just after you replied, my wee schnauzer became ill and then it was my turn. So I’ve just now come back to this.

Thank you so much for your help. I didn’t realize that I could just copy from the graph. Awesome. But for the colours, I’m not quite sure what you mean here. I’ve tried using y=g(x), but it just comes up with an exclamation symbol. I tried g(x)=y=2/3x+5 {-3<x<2}, but then when I drew the graph it remained invisible. Any chance you could actually show me what you mean with the first line and I can take it from there?

Again, really sorry not to have gotten back to you earlier and I very much appreciate your help.

No worries! Hope you and the dog are better.

So, instead of just having g(x) by itself in the graph, if you set (for example) g(x)=3x, then make this invisible, you can then use y=g(x) and control the colour, thickness, etc. of the line. When you run this as an activity, g(x) will be overwritten by the CL, but the properties you set earlier will remain.

I’ve done the first as an example in Slide 9 here: Sandbox / Testing • Activity Builder by Desmos

No worries, I did it!!!

Again, just many thanks for your help!!!

Awesome, and we’re all good now, thanks!!

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