Khan Academy: Addition & Subtraction: Find the Missing Value

Beginning a "handful of fairly simple inequality videos," Sal demonstrates a few inequality problems in which mathematicians need to add or subtract. Though he states that his goal is to familiarize viewers with the notation, his...

Sal solves some missing value problems: -1 = 7 - __ and -10 + __ = -5 and 4 = -2 + __ and 6 + __ = -8.

Sal solves more missing value problems: 4 = -8 - __ and __ - (-2) = -7 and -4 = __ - 9.

Practice finding the missing value in an addition or subtraction equation involving negative numbers. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

In this exercise, students practice addition and subtraction word problems 2. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.

Practice solving addition and subtraction problems with integers (positive and negative numbers). Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

Practice solving addition and subtraction problems with integers (positive and negative numbers).

This video explains place value in decimal numbers. Practice problems are available. [4:00]

In this video [3:37] learn how the Boys & Girls Club of Chaffee County uses Khan Academy in its math programs in Colorado.

Review the basic of adding negative numbers and try some practice problems.