Perimeter & Area Geometry

Rectangle W (width) Perimeter P=2l +2w Area A=lw l (length)

Square Perimeter P=4s Area A=s2 S (side)

Parallelogram height base Perimeter P=2l +2w Area A=bh

Triangle Perimeter P=a+b+c Area A= ½ bh a c h (height) b (base)

Trapezoid Perimeter= Add the distance of the sides Base 1 height height (base 1 + base 2) 2 Base 2 Perimeter= Add the distance of the sides Area= height(base 1 + base 2) 2

Circle Diameter d=2r Circumference C=2πr Area A=πr2 diameter radius

Example: Find the perim. & area of the figure. P=2l +2w P=2(5in)+2(3in) P=10in+6in P=16in A=lw A=(5in)(3in) A=15in2 5 in 3 in

Ex: Find the perim. & area of the figure. P=4s P=4(20m) P=80m A=s2 A=(20m)2 A=400m2 20 m

Ex: Find the perim. & area of the figure. P= 2(20in)+2(9in) A= b x h P=40in+18in A= (20in)(8in) P=58in A= 160in2

Ex: Find the perim. & area of the figure. P=a+b+c P=5ft+7ft+6ft P=18 ft A= ½ bh A= ½ (7ft)(4ft) A= ½ (28ft2) A= 14ft2 5 ft 4 ft 7 ft 6 ft

Ex: Find the perim. & area of the figure. A= 10ft(12ft+15ft) 2 P= 11ft+12ft+11ft+15ft P= 49 ft A= 270ft 2 A= 135 ft

Ex: Find the circumference & area of the circle. C=2πr C=2π(5in) C=10π in C≈31.4 in A=πr2 A=π(5in)2 A=25π in2 A≈78.5 in2 10in