And peace be upon you, too. وَعَلَيْكُمُ ٱلسَّلَامُ
You should use the "Calculated" question type.
The equation to solve is:
\[{ax=bx+c}\]
Rearranging, we have:
\[{x=\dfrac{c}{a-b}}\]
Let \({a-b}\) be equal to a positive integer, say:
\[{a=b+d}\]
Where \({x}\), \({b}\) and \({d}\) are random positive integers from three ranges (identical or different from one another), for example:
\[{x=\{3:13\}}\]
\[{b=\{3:13\}}\]
\[{d=\{3:13\}}\]
To write the equation in the question text, it is easier to use MathML rather than LaTeX because LaTeX has {} which interferes with the variables of the Calculated question, while MathML does not have {}.
The HTML code of the question text should therefore look like this:
<p>
Solve the following equation for <math style="font-family:stix"><mstyle mathsize="18px"><mi>x</mi></mstyle></math>:
</p>
<p style="text-align:center;">
<math style="font-family:stix"><mstyle mathsize="18px"><mn>{=({b}+{d})}</mn><mi>x</mi><mo>=</mo><mn>{b}</mn><mi>x</mi><mo>+</mo><mn>{={x}*{d}}</mn></mstyle></math>
</p>
The rest is pretty standard. I have attached an XML file for your question.