Collocations for equation - noun

basic, simple
This can be shown by a simple equation.

complex, complicated
algebraic, math (AmE), mathematical
differential, quadratic, simultaneous, etc.

solve, work out
I could not find a way of solving the equation.

derive, obtain
The ideal gas equation is derived from this model.

satisfy
the range of values of x which would satisfy this equation

balance
write

equation for
the equation for a straight line

a side of the equation
the numbers on the right-hand side of the equation

be a part of, come into, enter, enter into
The availability of water is also part of the equation.
Money also comes into the equation.