Diket selimut suatu tabung 528 cm² jika tinggi tabung 12 cm dan phi 22/7 hitung lah pqnjqng jari jari alasnya!

Dik. Luas selimut tabung (Lst) = 528 cm^2, tinggi = 12cm & phi = 22/7.
Dit. Jari jari?

Jawab...

Luas selimut tabung(Lst) = 2 × phi × r × t
@ Lst = 2 × 22/7 × r × t
@ 528 = 2 × 22/7 × r × 12
@ 528 = 22/7 × 24 × r
@ 528 × 7/22 = 24 × r
@ 168 = 24 × r
@ r = 168/24
@ r = 7cm

Semoga membantu.. ^_^