2. 7 th Grade Math Obj. 4c

3. Surface Area is the amount of exposed area on a 3-D object. Surface Area is always measured in square units, just like Area is.

4. Nets can be used to determine Surface Area. If an object has flat faces, its Surface Area can be determined by finding the area of each face and adding them together.

5. When you wrap a present, you’re working with Surface Area and Nets. Surface Area… Used in “Everyday” Life.

6. We can use our knowledge of nets to calcualte Surface Area…

7. Step 1: Unfold the figure by drawing it’s net. Step 2: Find the area of each shape using formulas learned previously.  Squares – l x w  Triangles - ½ hb Step 3: Add all of the figures areas together to get the total amount of area or surface area.

8.  Rectangular Prism 14 cm 2 cm 8 cm 14 cm 2 cm 8 cm 2 cm x 14 cm = 28 cm 2 2 cm x 8 cm = 16 cm 2 8 cm x 14 cm = 112 cm 2 cm2 + 156 cm 2 312 cm 2 + 2 =

9.  Rectangular Prism 14 cm 2 cm 8 cm Find the area of each shape & add Them together. = 2(14)(2) + 2(14)(8) + 2(2)(8) = 2(28) + 2(112) + 2(16) = 56 + 224 + 32 = 312 in 2

10.  Pyramid Find the surface area of the pyramid, by finding the area of each side and add them together. 9 cm 8 cm Triangular Sides: A=1/2(B)(H) A= ½(8)(9) A = 36 sq. cm Base: A= L x W A= 8(8) A= 64 sq. Cm Base for the pyramid: 64+36+36+36+36= 208 sq. cm

11. 1.A rectangular prism with a length of 10, a width of 5 and a height of 3. 1.A square pyramid with a base of 5 and a slant height of 6.

12. 1.A rectangular prism with a length of 10, a width of 5 and a height of 3. 1.A square pyramid with a base of 5 and a slant height of 6. 190 85