Finding Surface Area Step 1: Flatten the 3-D figure A rectangular prism will flatten to 6 rectangles. Depending on the dimensions of the 3-D figure, you will have different size rectangles. Rectangular Prism
Finding Surface Area Step 2: Transfer the dimensions to the 3-D figure Dimensions: Length – 12 (the longest side) Height – 8 (top to bottom) Width – 4 (front to back) Rectangular Prism Height 8 Length 12 Width 4
Finding Surface Area Step 3: Transfer the dimensions from the 3-D figure to the flattened figure Dimensions: Length – 12 (the longest side) Height – 8 (top to bottom) Width – 4 (front to back) Rectangular Prism Height 8 Length 12 Width
Finding Surface Area Step 4: Find the AREA for each rectangle. (Length X Width) Rectangular Prism Height 8 Length 12 Width x 4 12 x 8 12 x 4 12 x 8 8 x 4 48 sq units 96 sq units 48 sq units 96 sq units32
Finding Surface Area Step 4: Find the TOTAL SURFACE AREA for the 3-D Figure Add together the areas for each rectangle Rectangular Prism sq units 96 sq units 48 sq units 96 sq units = 352 sq. units Total surface area
Cube or Square A cube or square will flatten to 6 equal squares.
Triangular Prism A triangular prism will flatten to 3 rectangles and two equal triangles. Step 1: Flatten the 3-D figure
Triangular Prism The 2 triangles will form a rectangle Step 2: Transfer the dimensions to the 3-D Figure Dimension: Base = 4 Height = 6 Hypotenuse = 12 Length = 10
Triangular Prism Transfer dimensions to Flattened Figure Step 3: 4 6
Triangular Prism Find the area for each rectangle and triangle Step 4: 8 6 Step 5: Write the area inside the specific shape A = 8 x 15 A = 10 x 15 A = 6 x A = 6 x
Triangular Prism Add all the areas for the total surface area Step 6: =Total surface area