Every type and branch of math have concepts and formulas which are important in doing calculations. Here are a couple examples of them for finding and calculating certain values in math:

A core part of Algebra is factoring and solving for values of variables based on the values of variables that we already know.

Geometry relies on shapes, and being able to figure out values of certain parts of shapes is vital. A common example of a formula in geometry (trigonometry) is a^2 + b^2 = c^2, with a and b being the measures of the legs on a right triangle, and c being the measure of the hypotenuse (long side) of a right triangle (triangle with a 90° interior angle).

Calculus consists of various factors to be used in calculating such as derivatives, integrals, and limits, with the former 2 being used in the equations below.