Find the Area of Rectilinear Shapes

(D) Decompose composite figures formed by rectangles into non-overlapping rectangles to determine the area of the original figure using the additive property of area

3.MD.7 Relate area to the operations of multiplication and addition.

3.MD.7.D Recognize area as additive. Find areas of rectilinear figures by decomposing them into non-overlapping rectangles and adding the areas of the non-overlapping parts, applying this technique to solve real world problems.