Hello,

I just discovered Moodle a few weeks ago and am very happy about it so far. My question (for which I couldn't find an answer anywhere in the forum and with Google) regards the possibility to let students exercise the procedure of equation solving in a Moodle quize. By that I mean not solve the problem with pen and paper and then enter the answer in Moodle, but enter all steps.

For example, the quiz question could be "Solve this equation: 2x + 3 = 18 - x

Then I would like the student to be able to work in several steps:

* 2x = 15 - x

* 3x = 15

* x = 5

Maybe there could even be feedback after each step (like: you're on the right track, but not yet finished).

Is this possible in Moodle?

Thanks in advance!

Sander

### How to train students in equation solving step by step

Number of replies: 4### Re: How to train students in equation solving step by step

I guess you can plug moodle into a symbolic manipulator, but what do you want exactly? There are many ways to solve an equation, depending on which simplification you do at each step.

With a CAS, you can check that the equation is the same at each step but then, how do you want to measure progress? I guess you could use the lenght of the total expression as a rough indicator, but that may be misleading.

Regards

With a CAS, you can check that the equation is the same at each step but then, how do you want to measure progress? I guess you could use the lenght of the total expression as a rough indicator, but that may be misleading.

Regards

### Re: How to train students in equation solving step by step

Thanks for your reply. The progress indication is not really necessary. I want my students to be able to enter the steps they make, and like you say a check should be done to ensure that they entered an equivalent equation.

### Re: How to train students in equation solving step by step

It is possible to write a sort of editor for that and embed it in a Moodle quiz question. Such an editor may allow the students to enter steps which consists in an equation and a rule by which the equation was deduced from the preceding one. Of course you have to define the rules. These rules are basically rules of equivalence of equations.

So for instance you can move from

2x + 3 = 18 - x

to

2x = 18 - x - 3

by moving the +3 from the left side to the right side where it becomes -3. So one general rule of equivalence may be called 'contra-position' and allow you to move a constant or variable from one side to the other with a change of sign.

Then, you can move from

2x = 18 - x - 3

to

2x = 15 - x

by applying a rule of subtraction which allow for one subtraction in the equation of one constant or coefficient from another.

The editor simply checks that the equation in each step can be validly deduced from the preceding step by the specified rule. Then, if the solution starts from the given equation, arrives at the a proper result, that is, an equation of the form x = 5, and all the steps are validly deduced, it is correct.

So for instance you can move from

2x + 3 = 18 - x

to

2x = 18 - x - 3

by moving the +3 from the left side to the right side where it becomes -3. So one general rule of equivalence may be called 'contra-position' and allow you to move a constant or variable from one side to the other with a change of sign.

Then, you can move from

2x = 18 - x - 3

to

2x = 15 - x

by applying a rule of subtraction which allow for one subtraction in the equation of one constant or coefficient from another.

The editor simply checks that the equation in each step can be validly deduced from the preceding step by the specified rule. Then, if the solution starts from the given equation, arrives at the a proper result, that is, an equation of the form x = 5, and all the steps are validly deduced, it is correct.

### Re: How to train students in equation solving step by step

We use SCORM compliant packages at http://www.stmichaelcollege.nl/sage/ (in dutch however)