2. Bell Work Find the surface area of the figure. 6 x 4 = 24 in² 3 x 4 = 12 in² 6 x 3= 18 in² Add them up! SA = 24 + 24 + 12 + 12+ 18 + 18 SA = 108 in²

3. Surface Area Using the Formula

4. Surface Area What does it mean to you? Does it have anything to do with what is inside of the prism? Surface area is found by finding the area of all the sides and then adding those answers up. How will the answer be labeled? Units 2 because it’s area!

5. Shortcut for surface Area You can find the SA of any prism by using the basic formula for SA which is: SA= 2B + Ph Ph = perimeter of the base x height B = the area of the base of the prism.

6. Let’s start with a rectangular prism. You can find the area for each surface and add them up, or surface area can be done using the formula. SA = 2lw + 2lh + 2wh OR SA = 2B + Ph Either method will give you the same answer.

7. Top/bottom 2(8)(4) = 64 Left/right 2(4)(7) = 56 Front/back 2(8)(7) = 112 Add them up! SA = 232 cm² Example: Find the area of each face 7 cm 4 cm 8 cm SA= 2B + Ph B = (7)(4) = 28 P = 4 + 4 + 7 + 7 = 22 h = 8 SA= 2(28) + 22(8) SA= 56 + 176 SA = 232 cm² OR

8. Example: 8mm 9mm 6 mm 6mm Find the AREA of each SURFACE 1. Top and bottom triangle: A = 2(½ bh) A =2( ½ )(6)(6) A = 36 2. The two sides are the same. A = 2lw A = 2(6)(9) A = 108 3. The back rectangle is different A = lw A = 8(9) A = 72 4. ADD THEM ALL UP! 36+ 108+ 72 SA = 216 mm² SA= 2B + Ph SA= 2(18) + 20(9) SA= 36 + 180 SA = 216 mm² OR B = ( ½ )(6)(6) = 18 P = 6 + 6 + 8 = 20 h = 9

9. Cube Are all the faces the same? YES 4m How many faces are there?6 Find the Surface area of one of the faces. 4 x 4 = 16Take that times the number of faces. X 6 96 m 2 SA for a cube.

10. You try SA= 2B + Ph SA= 2(16) + 20(15) SA = 32 + 300 SA= 332 in² B = 2 x 8 = 16 in² P = 2 + 2 + 8 +8 = 20 in Find the Surface Area

11. Practice Worksheet on Surface area