What equation format do I select for my equation?
The 
"Advanced" format with manual input can be used equally well for simple equations in the form ax + b = c and ax + b = cx + d and for 
more complex linear equations, including equations with parentheses, fractions, and decimals.
For linear equations in the forms 
ax + b = c and 
ax + b = cx + d you can also use the built-in templates.
You can select the necessary format in the Settings window.
