October 15, 2008

This resource has been contributed by Winpossible, and can also be accessed on their website by clicking here - Identify mistakes in order of operations.

It explains how to identify mistakes in the order of operations in a multi-step derivation. Using examples, it explains that we have to follow the order of operations PEMDAS (Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction). Simply put, when we have to simplify any expression, we should first perform any calculations inside parentheses, and then perform all multiplication and division operations working from left to right, and lastly perform all addition and subtraction from left to right.

For example, when we solve the equation 3(x + 5) = 2x + 35, the steps are:

It explains how to identify mistakes in the order of operations in a multi-step derivation. Using examples, it explains that we have to follow the order of operations PEMDAS (Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction). Simply put, when we have to simplify any expression, we should first perform any calculations inside parentheses, and then perform all multiplication and division operations working from left to right, and lastly perform all addition and subtraction from left to right.

For example, when we solve the equation 3(x + 5) = 2x + 35, the steps are:

- Step 1 3x + 15 = 2x + 35
- Step 2 5x + 15 = 35
- Step 3 5x = 20
- Step 4 x = 4

This FREE mini-lesson is a part of Winpossible's online course that covers all topics within Algebra I. Click on the video below to go through it. If you like it, you can buy our online course in Algebra I by clicking here.

- Mathematics > General
- Mathematics > Algebra
- Education > General

- Grade 9
- Grade 10

Apply properties of operations as strategies to add and subtract.

Identify arithmetic patterns (including patterns in the addition table or multiplication table), and explain them using properties of operations.

Generate a number or shape pattern that follows a given rule. Identify apparent features of the pattern that were not explicit in the rule itself.

Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.

Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.

apply properties of operations to add and subtract two or three numbers.