A rectangle has side lengths of seven and 12. Jennifer has decomposed it and used the distributive property to help her find the area. She multiplies seven times 10 and seven times two and says the area is 84 square units. What expression shows this?
We can use this picture to help us write an expression. Our first image is the whole rectangle with side lengths seven and 12. To find the area of this rectangle, we would multiply seven times 12. But Jennifer decomposed it into two pieces.
Our large rectangle, seven times 12, is equal to seven times 10 plus seven times two. Let’s write this expression again just to make it a little bit more clear. Seven times 12 equals seven times 10 plus seven times two.