Before you create an equation question, it might be helpful to understand the general outline of an exam question. We explain that in the Creating a question article.
From the Designer page, click on new question. From the top right corner, click on the Add new question button.
From the blocks bar, click on the Equation block, Then click on the Add an equation button to open the equation editor.
Here you have two options (click on the tab to see the details):
Latex text
Uploading an image
Latex Text: Here you can use the Latex editor to write your equation. And to make it easier, you can use the virtual keyboard by clicking on the keyboard icon from the top right corner.
After you finish writing your equation, click on the Done button.
Click on Save changes and you will see the question in the questions list.