Combining Like Terms

Questions
1

Hello All,
Very new to the CL but see many opportunities!

I would like to use the graphing component to validate students understanding of simplifying equations. It seems like I could just check the slope and intercept of any equation they enter and confirm whether their equation is equivalent or not to some target equation. But I want to turn off the graph and only expose the equation part of the calculator. Is that possible?

Thank You,
Mike

2

I hope I understood your question.
You can always hide graph and still use it as calculator even though it is hidden.

3

You can’t have the expression list only for a graph, only vice versa. You may want to use a table instead, using parseEquation( ).differenceFunction( ) to either import into a hidden graph for comparing functions, or using evaluateAt(equation solution)=0 in the CL.

4

Thank you for your help. I ended up using xyline in a table component. I obviously need to do more checks and make sure there is only 1 x term etc… but this will work eventually.

5

You didn’t publish yet, so it’s a blank activity.

Look into countNumberUsage for checking for specific numbers

6

Thank you. I tried countNumberUsage but there is no way to check for the number of x or y terms in the equation. I think I need RegEx or one of the patter functions that aren’t public yet.

7

If you pair xyLine with countNumberUsage, you should have all the checking that you need. You may even use simpleFunction with evaluateAt.

8

countNumberUsage doesn’t look for number of terms, it searches for how many of a particular value (or how many numbers total are used). For example, 3x-5x+4 vs -2x+4.

f=simpleFunction(this.latex)
correct=f.evaluateAt(4)=-8 and f.evaluateAt(0)=4 
  and countNumberUsage(this.latex)=2  #checks that there are only 2 numbers used
                             #you can also use inequalities (perhaps for x vs 1x)
  and countNumberUsage(this.latex,2)=1 #checks for the presence of one 2 (doesn't matter that it's negative)
  and countNumberUsage(this.latex,4)=1 #checks for one 4

3x-5x+4 would be marked incorrect due to the lack of a 2. You can use variables for the second parameter, but would need to make sure you account for the case where the coefficient and constant are equivalent.

9

Thanks for your help. This is an evolving project but I did want to update everyone. There are some obvious bugs (string spaces?!) and more relevant feedback to the student. I am making use of evaluateAt for the expressions in x and y along with counterNumberUsage to check the number of terms. And I am using xyline for the equations of a line and also checking the LHS is y.

I have different templates for evaluating input expressions and equations. I will keep extending this to different forms of a line and adding more input. I do wish there was some sort of a loop variable to avoid repeating the same line of code n times but this will work.

Thank you,
Mike

10

In reference to latex? You can use backticks instead.