Negative Times Positive
Part of the Numbers & Operations section of Coddy's Pre-Algebra journey. Lesson 28 of 60.
Multiplying by a whole number is repeated addition: 3 × 5 is three 5s. That works for a negative number too. (-4) × 3 is three -4s added together, -4 + (-4) + (-4), which is -12.
On the number line, that is three jumps of 4 to the left, ending at -12. In money: owing 4 dollars to each of three friends means you owe 12 in all. The size is the ordinary product, 4 times 3, and the sign is negative.
The order of the factors still does not matter, so 3 × (-4) is -12 as well. A negative times a positive is negative, whichever comes first.
Challenge
Work out (-7) × 6.
Try it yourself
Simplify the expression
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Numbers & Operations
1Working on the Board
Your First AnswerType the Next LineOne Line at a TimeDots and BarsFriendly ProductsRecap: Board Work4Adding Integers
Adding Two NegativesDifferent SignsZero PairsAdding Several IntegersRecap: Adding Integers2Order of Operations
Multiply Before AddingLeft to RightParentheses FirstBrackets Inside BracketsThe Fraction Bar GroupsRecap: Order of Operations5Subtracting Integers
Add the OppositeSubtracting a NegativePlus and Minus in a RowDistance Between NumbersRecap: Subtracting Integers6Multiplying and Dividing
Negative Times PositiveTwo NegativesCounting the NegativesDividing IntegersZero in DivisionRecap: Multiply and Divide