I like to use the mnemonic “Please Excuse My Dear Aunt Sally” or PEMDAS to remember the order. The order is Parentheses,Exponents, Multiplication and Division (either one, in order from left to right), and then Addition and Subtraction (either one, in order from left to right) – PEMDAS.
My Dear Aunt Sally
PEMDAS stands for:
So you’ll do the math left to right, like you’re reading a book, but you must pay careful attention and perform some operations before others. Here are some examples:
I thought I’d start something new and provide some of my “corny” math tips that I provide to my students. Here’s one that helps me remember the equations for horizontal and vertical lines, and can be found in the Coordinate System and Graphing Lines section:
Horizontal lines are when “y = a number”; for example, “y = 5” (with no “x” in the equation) is a horizontal line where y equals 5. The slope is zero (0), since 0x means there is no x. You can remember this since a “y” looks like an upside down “h”, and “h” is the beginning of the word “horizontal”. The line “y = 0” sits on the x axis.
Vertical lines are when “x = a number”; for example, “x = –2″ (with no “y” in the equation) is a vertical line where x equals –2. The slope is undefined, like the line is falling from the sky. You can remember this since you can draw a “v” in an “x”, and “v” is the beginning of the word “vertical”. The line “x = 0” sits on the y axis.