|
by MizzterG Welcome Rutherford County Students Surface area of cubes You will not be able to change your answers after clicking ok. Read each slide carefully. Enter answers as needed. Be sure of your answer before clicking OK. Surface area of cubes Some slides will require you to drag answers to a spot. You can move the answers after they are dropped until you click ok. Surface area of cubes shift + tab will make make the cursor go back to the last box When answering, it is sometimes easier to use the tab key, type the answer, and press the enter key. Just be carefully you don't hit keys too fast. Blank answers area wrong. Surface area of cubes Using just the mouse will be slow. So basically, you have six squares. Each face of a cube is a square area of a square is side times side Let's decompose this shape a bit more so you can see. A = S • S We know how to find the area of a square. This will help us with the surface area of the entire shape. To decompose a shape means to separate its parts. de•com•pose To decompose a shape means to separate its parts. de•com•pose You can now see the face (square) separate from the cube. de•com•pose to separate into parts The area of the square is easy to find. de•com•pose to separate into parts 1 unit 1 unit The formula for area of a square is side x side de•com•pose 1•1= to separate into parts unit2 1 unit 1 unit The formula for area of a square is side x side de•com•pose 1•1= to separate into parts 1 1unit2 unit2 1 unit 1 unit The formula for area of a square is side x side When we recompose the shape, you can see each of the visable faces has an area of 1 square unit. de•com•pose to separate into parts 1unit2 1unit2 It can also be written 1 unit2 1unit2 1 unit 1 unit The formula for area of a square is side x side There are three square units visible. But wait! Don't forget a cube has six faces! There are three faces you can's see. Surface Area the area covering the whole shape 1unit2 1unit2 1unit2 1 unit 1 unit The 1 unit2 1 unit2 1 unit2 1 unit2 1 unit2 1 unit2 6 unit2 cube ? has a Surface Area the area covering the whole shape surface ? 1unit2 1unit2 area ? 1unit2 1 unit of 1 unit 6 square ? The formula for area of a square is side x side units ? . The 1 unit2 1 unit2 1 unit2 1 unit2 1 unit2 1 unit2 6 unit2 cube has a Surface Area the area covering the whole shape surface area 1unit2 1unit2 1unit2 1 unit of 1 unit 6 square units The formula for area of a square is side x side . 6 unit2 1 unit2 1 unit2 1 unit2 1 unit2 1 unit2 1 unit2 Surface Area the area covering the whole shape length 1unit2 1unit2 1unit2 width height This formula works for cubes and rectangular prisms The formula for area of a square is side x side or l x w . You can find the of a by finding ↽ the area of one and by . Surface area of a cube side ? surface ? area ? multiplying ? If you know its a cube, this is the quickest way to find the surface area. cube ? six ? You can find the of a by finding the area of one and by . (S • S) •6 = surface area of a cube side surface area multiplying cube If you know its a cube, this is the quickest way to find the surface area. six side x side x 6 The formula can be written in different ways, but they all mean the same thing. surface area of a cube= 6s2 or 6(s • s) de•com•pose to separate into parts You can also find surface area using a net. click ok 15 times quickly to see the cube transform into a net. You're doing great! 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 STOP continue at normal speed 0 This is a of a . net ? cube ? A net is a two-dimensional pattern of a three-dimensional figure. This is a of a . net cube A _____ is a ________________ pattern of a . ______________ _____________. three-dimensional ? This is a of a . net ? two-dimensional ? net figure ? cube three-dimensional A _____ is a ________________ pattern of a . ______________ _____________. This is a of a . net two-dimensional net figure cube Taking a look at this net, you can see it is the net of a cube. That means all sides are the same. 1 unit Taking a look at this net, you can see it is the net of a cube. That means all sides are the same. 1mm2 1 mm 1 mm What are the areas of the other squares? mm2 mm2 mm2 mm2 mm2 All sides are the same. 1mm2 1 mm 1 mm Add all the areas to find the surface area of the cube. The cube has a surface area of 1 mm2 1 mm2 1 1 1 mm2 mm2 mm2 1mm2 1 mm 1 mm mm2 Add all the areas to find the surface area of the cube. The cube has a surface area of 1 mm2 1 mm2 1 1 1 mm2 mm2 mm2 1mm2 1 mm 6 • 1 = 6 6 1 mm mm2 surface area of a cube = What is the surface area of this cube? (s x s) 6 2cm (S • S) • 6 formula Find the area of one face (side) then multiply by six. surface area of a cube = (s x s) 6 2cm cm2 2cm (S • S) • 6 surface area of a cube = formula Find the area of the rest of the faces. cm2 cm2 cm2 cm2 cm2 (s x s) 6 4 2cm cm2 2cm (S • S) • 6 formula What is the surface are of the entire cube? surface area of a cube = 4 cm2 4 cm2 cm2 4 4 4 cm2 cm2 cm2 (s x s) 6 4 2cm cm2 2cm (S • S) • 6 formula (2 • 2) • 6 4 cm2 4 24 cm2 cm2 (4) • 6 = 24 4 4 4 cm2 cm2 cm2 4 2cm cm2 2cm 9 in2 81 in2 63 in2 54 in2 surface area of a cube = 3in You can use scratch paper and a calculator. What is the surface area of this cube? (s x s) 6 54 in2 surface area of a cube = 3in (3 x 3) x 6 You can use scratch paper and a calculator. What is the surface area of this cube? (s x s) 6 surface area of a cube = What is the surface area of the cube? 5 ft 25 square feet 150 square feet 125 square feet 200 square feet (s x s) 6 What is the surface area of the cube? surface area of a cube = 5 ft (5 x 5) x 6 25 x 6 = 150 (s x s) 6 150 square feet surface area of a cube = Sometimes you might not get a picture. Just use the formula. (s x s) 6 or (s x s) 6 surface area of a cube = A cube has a side measuring 8 mm. What is its surface area? 800 square millimeters 384 square inches 512 square millimeters 16 square millimeters (s x s) 6 A cube has a side measuring 8 mm. What is its surface area? surface area of a cube = (8 x 8) x 6 384 square inches (s x s) 6 Bob has a present he wants to wrap. The present is a cube that has a side measuring 6 inches. How many inches of wrapping paper does he need? surface area of a cube = 1263 square inches 36 square inches 24 square inches 216 square inches (s x s) 6 Bob has a present he wants to wrap. The present is a cube that has a side measuring 6 inches. How many inches of wrapping paper does he need? (6x6) x 6 surface area of a cube = 216 square inches (s x s) 6 Here are some other sites where you can do some practice. Hope this lesson and quiz helped you understand the surface area of a cube! |