CONESCONES

PYRIMIDSPYRIMIDS

ANDAND

Jim Smith JCHSJim Smith JCHS

PARTS OF A PYRIMIDPARTS OF A PYRIMID( SQUARE BASE )( SQUARE BASE )

BASE EDGEBASE EDGE

BASE EDGEBASE EDGE

HEIGHTHEIGHT ( h ) ( h )

SLANT HEIGHT ( SLANT HEIGHT ( ll ) )

PARTS OF CONESPARTS OF CONES

HEIGHT ( h )HEIGHT ( h )

rr

SLANT HEIGHT ( SLANT HEIGHT ( ll ) )

LA = LA = ½½ p p ll

SA = LA + BSA = LA + B

VOL= VOL= ⅓⅓ B h B h

FIND THE PERIMETERFIND THE PERIMETER AND AREA FIRSTAND AREA FIRST

1212

Base edge Base edge hh sl sl 12 12 88 1010

P = 12 + 12 + 12 + 12 = 48P = 12 + 12 + 12 + 12 = 48B = 12 x 12 = 144B = 12 x 12 = 144

LA = ½ p l = ½ x 48 x 10 = LA = ½ p l = ½ x 48 x 10 = 240 sq un240 sq unSA = LA + B = 240 + 144 = SA = LA + B = 240 + 144 = 384 sq un384 sq unVOL = ⅓VOL = ⅓ B x h = B x h = ⅓⅓ 144 x 8 = 144 x 8 = 384 cu un384 cu un

33

r r hh slsl3 3 44 55

p = 2 p = 2 ππ r = r = 2 2 ππ 3 = 6 3 = 6 ππB = B = ππ r r² = ² = ππ 3² = 9 3² = 9 ππ

LA = ½ p l = ½ x 6 LA = ½ p l = ½ x 6 ππ x 5 = 15 x 5 = 15 ππ sq unsq un

SA = LA + B = 15 SA = LA + B = 15 ππ + 9 + 9 ππ = 24 = 24 ππ sq unsq un

VOL = ⅓ B h = ⅓ x 9 VOL = ⅓ B h = ⅓ x 9 ππ x 4 = 12 x 4 = 12 ππ cu uncu un