# Check a quadratic equation and ordered pair in a table

We are working on quadratics in standard and vertex form and finding zeros and vertex. I would like to be able to check that an equation that they have typed into the table is correct same with an ordered pair. I don’t know if it would be better to have them in a different component. Here is the slide I am trying to get to work.

Thanks in advance for any help!

Since you want them to have a particular form, I recommend using countNumberUsage for the h and k (though I didn’t need the negative for the k). If you don’t check the form somehow, they will be able to just enter the given form to get a check for three points matching.

Since it’s a quadratic, it’s uniquely defined with 3 ordered pairs, so maybe check three points.

When I’m filling in a table as a student, I am happier if there’s not an x by my work where I’m typing, so I added more conditionals on the suffix.

``````f = simpleFunction("x^{2}+6x-2")
input = simpleFunction(this.cellContent(1,2))

check12 =
f.evaluateAt(0)=input.evaluateAt(0) and
f.evaluateAt(1)=input.evaluateAt(1) and
f.evaluateAt(2)=input.evaluateAt(2) and
countNumberUsage(this.cellContent(1,2),3)=1 and
countNumberUsage(this.cellContent(1,2),11)=1

cellSuffix(1,2):
when this.cellHasFocus(1,2) or this.cellContent(1,2)="" or button8.timeSincePress = 0 ""
otherwise when check12 "✅" otherwise "❌"
``````
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Thank you so much for your help! This worked perfectly!!! As always, I appreciate the help from this Desmos community