Slide 1

We are learning tofind the area of parallelograms and trapezoids. Thursday, January 15, 2015 Slide 2 TrapezoidsParallelograms 4 sided objects (quadrilaterals) Two sets of parallel sides One set of parallel sides Slide 3 Height (distance between bases) Slant Length Base (either parallel side) By cutting a parallelogram along the height the shape can become a Rectangle! Area = (Base)(Height) Slide 4 7 cm 5 cm 4 cm 13 ft 12 ft 20 ft 9 ft 10 ft 35 ft Area = (base)(height) Area = (4)(7) Area = 28 square cm Area = (base)(height) Area = (12)(20) Area = 240 square ft Area = (base)(height) Area = (35)(9) Area = 315 square ft Slide 5 Base 1 or b 1 Base 2 or b 2 Height b2b2 b1b1 Take two of the same trapezoids and put them together to make a parallelogrambecause we know how to find the area of a parallelogram. b 1 + b 2 Formula: Area = (Base)(Height) Formula: Area = (b 1 + b 2 )(Height) We dont need the whole parallelogramwe ONLY NEED: Formula: Area = ()(b 1 + b 2 )(Height) Slide 6 4 ft 5 ft 6 ft 14 ft Area = ()(b 1 + b 2 )(Height) Area = ()(14 + 6)(4) Area = ()(20)(4) Area = (10)(4) Area = 40 square feet When you are done with finding the area of the last trapezoid let your teacher know so they can check your work and give youre the homework assignment