Unit3-Lesson4Pt2-The Cuboid

1. UNIT3: LESSON 4 SECOND:THE CUBOID Mr.Mostafa Kadry

2. THE LATERAL AREA AND TOTAL AREA OF THE CUBOID. Mr.Mostafa Kadry

3. THE CUBOID Remember that: It has 6 faces , each face is a rectangle and two opposite faces are equal in area. The area of the rectangle = Length × width. It has 8 vertices and 12 edges. It has 3 dimensions “Length ,width ,height” Its V= Length × Width × Height Mr.Mostafa Kadry

4. A carton box in the form of cube We unfold this cube as in fig(2) Fig(2) Fig(1) Mr.Mostafa Kadry B BASE BASE

5. THE LATERAL ARES OF A CUBOID The L.S.A. of a cuboid is the sum of the areas of its four lateral faces which are perpendicular to Base. Face(1) Face(3) Face(2) Base Base Face(4) Mr.Mostafa Kadry H(height)

6. SO , THE L.S.A. OF A CUBOID = The area of (F1+F2+F3+F4) = AB × H + BC × H + CD × H + DA × H = (AB+BC+CD+DA) × H = Perimeter of the base × H Mr.Mostafa Kadry

7. WE DEDUCE THAT: ÷ × L.S.A. OF CUBOID THE PERIMETER OF THE BASE THE HEIGHT Mr.Mostafa Kadry

8. THE TOTAL AREA OF A CUBOID The T.S.A. of a cuboid is the sum of the areas of ALL FACES Face(1) Face(3) Face(2) Base Base Face(4) Mr.Mostafa Kadry H(height)

9. SO , THE T.S.A. OF A CUBOID =The lateral area + 2 × (the area of the base) Notice that : If a cuboid without a lid , then : The T.S.A. Of cuboid = L.S.A. + The area of one B Mr.Mostafa Kadry

10. EXAMPLES 1- A cuboid – shaped box is 4 cm. long , 3 cm. wide and 5 cm. high , find : The lateral area. The total area. Mr.Mostafa Kadry

11. Cuboid- iphone Mr.Mostafa Kadry

12. THANKS Introduced by MR. MOSTAFA KADRY MATH TEACHER 01002374750 [email protected] LinkedIn , FACEBOOK Twitter. Mr.Mostafa Kadry