Surface area 0506.4.4 Solve problems involving surface area and volume of rectangular prisms and polyhedral solids. Perimeter Measure each side Add all the sides together 13 cm P = 36 cm 5 cm Area Area of rectangles, triangles, and parallelograms. Rectangles: A = l x w Parallelograms: A = b x h Triangles: A = ½ b x h Find the area A = l x w A = 13 x 5 A = 65 sq cm 13 cm 5 cm Find the area 5 in 6 in 9 in A = 45 square in Remember the rectangle? A triangle is 1/2 5 in 3 in 3 in 5 in Find the area A=½bxh 6 in A = ½ x 7 in x 6 in 7 in A = 21 square in Surface area Think back to all our 3D shapes (polyhedra) Name a few faces When finding the surface area of a figure, you must measure all faces. You must know the length and width of each face. Once you have found those lengths, you must then find the area. Let’s take a look. Lets use a cube. A net of a cube Surface Area If you add together all of the areas from the faces of a 3-D shape, then the total is the surface area. It is the total amount of space needed to cover the outer surface of the shape. This is a property of 3-D shapes, and you might have noticed it when you've tried to figure out how much wrapping paper to use to wrap a present. Back to the cube We must measure each side before we can find the surface area. Lets say each side measures 5 cm. So the area of one face is??? 25 sq cm What else to do we need to know? How many faces are there? 6 faces total, so… 6 x 25 = 150 sq cm Formula Surface Area Of Rectangles (base x height + height x width + width x base) x 2 (b x h + h x w + w x b) x 2 Textbook page Do # 1-5 as group or on own. HW- Wb page 205 Crayon, color pencil boxes, or kleenex box. You will measure the length and Add them width of each face. (use sq cm) Label it with a sharpie. Find the area of each face and write the area in the center. Write the sums of each down to find the surface area of the box. Write this total on a sticky note. Compare total with a partner. 3 congruent faces… Did anyone notice that there are 3 congruent faces? Workbook page 205 Work with a partner Surface area 0506.4.4 Solve problems involving surface area and volume of rectangular prisms and polyhedral solids. Video http://www.pearsonsuccessnet.com/s npapp/learn/navigateIDP.do?method =vlo&internalId=130511100000126 Use the shape from last week. Measure each side and find the surface area. (like the boxes yesterday) Get with other students in the room with your shape. Present to the class as a group how you found the surface area and what it is. Classwork/Homework WB page 206 Possibly assign project Surface area 0506.4.4 Solve problems involving surface area and volume of rectangular prisms and polyhedral solids. Video online http://www.youtube.com/watch?v=rg 936mmOE1k&feature=related Walk through the steps Will need to stop and discuss Smiley guy - http://www.youtube.com/watch?v=kn lc6O6d8BU&NR=1&feature=endscr een Boy http://www.youtube.com/watch?v=d MUT-NY3gzM&feature=related Turn to page 328 in book # 6-10 with a partner HW – study guide http://www.ixl.com/math/grade- 5/surface-area Questions for review if you have time.