Jawabanmu

2014-03-27T09:16:32+07:00
D. panjang OA (jari-jari)
luas juring kuning = 154 cm ^{2}
 \frac{ 90^{o} }{360^{o} } .  \pi . r^{2} = 154 cm ^{2}
 \frac{1}{4}  .  \frac{22}{7} .  r^{2}   = 154 cm ^{2}
 r^{2} = 154 . 4. \frac{7}{22}
 r^{2} = 196

 r =  \sqrt{196}
 r = 14 cm

a. luas daerah berwarna hijau
= \frac{besar sudut}{360^{o} } .  \pi .  r^{2}
=  \frac{150}{360} .  \frac{22}{7} .  14^{2}
=  \frac{15}{36} .  \frac{22}{7} . 196
= 256, 7 cm ^{2}

b. luas daerah berwarna merah
= \frac{besar sudut}{360^{o} } .  \pi .  r^{2}
=  \frac{120}{360} .  \frac{22}{7} .  14^{2}
=  \frac{1}{3} .  \frac{22}{7} . 196
= 205,3 cm ^{2}

c. luas permukaan tripkles  = luas lingkaran
=  \pi .  r^{2}
=  \frac{22}{7} .  14^{2}
=  \frac{22}{7} . 196
= 616 cm ^{2}

e. keliling papan tripleks = keliling lingkaran
= 2. \pi . r
= 2.  \frac{22}{7} . 14
= 88 cm

semoga membantu :) jadikan yang terbaik ya :))








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2014-03-27T17:49:19+07:00
Meskipun kudrart mnyan 0 tetap jadi 5