1. 3.5 Surface Area of a Rectangular Prism Mme DiMarco

2. Learning Goal: use a formula to calculate the surface area of a rectangular prism Learning Goal

3. Formulas: Rectangle: A = b x h P = 2 x (b + h) Square: A = c 2 P = 4c Remember! b h s s

4.  Flat representation of all the faces of a polyhedron  Each face is connected to at least one other by a common edge Net of a Polyhedron

5. Surface area = the sum of the areas of each individual rectangle (the total area of the net) Surface area of a rectangular prism 3cm 8cm 5cm Area = 8 x 5 Area = 8 x 3 Area = 8 x 5 Area= 8 x 3 Area = 5 x 3 8cm3cm 5cm 3cm 5cm Area = 5 x 3 3cm 5cm 3cm

6. Step 1: find the area for each individual face on the rectangular prism Step 2: add each area to find the total area We can do both of these steps in one equation… A t = 2(8 x 3) + 2(8 x 5) + 2(3 x 5) A t = 2(24) + 2(40) + 2(15) A t = 48 + 80 +30 A t = 158cm 2 Surface area of a rectangular prism

7.  You can write the equation  A variable represents each letter…  Length = l  Width = w  Height = h Formula for area of a rectangular prism Aire = L x l Aire = L x h Aire = L x l Aire = L x h Aire = l x h h L l wh l h h l A t = 2lh + 2lw + 2hw

8.  Page 99, questions 1 à 3 Homework