The word MDAS stands for Multiplication, Division, Addition and Subtraction.
In this rule, multiplication and division are partners while addition and subtraction are partners. If there's an equation that contains all of those fundamental operations, you need to solve for the multiplication or division first. It's based on the equation if the multiplication will be ahead of division or vice versa but you need to solve for the first one (for example, multiplication) that will appear in the equation. And then after solving for the letters M and D, solve for the letters A and S which are the addition and subtraction. If the addition came first, then that's the first one that you will solve and vice versa.
Example:
2 + 16 x 2 - 14 / 7 + 5
2 + 16 x 2 - 14 / 7 + 5
2 + 30 - 2 + 5
32 - 2 + 5
30 + 5
35