Question

Help me !! pake care

Answer 1

Alas segitiga samasisi
La = 1/2.s.t ---> t = √s²-(1/2 s)²
= √s²-1/4 s²
= 1/2 s √3
= 1/2.20 √3
= 10√3
La = 1/2.20.10√3
= 100√3 cm²

jika tinggi sisi tegak limas 25cm
maka Luas sisi tegak

Lt = 1/2.s.T ---> T = √25²-10²
= √625-100
= √525
= 5√21
Lt = 1/2.20.5√21
= 50√21

Luas selimut = 3.Lt
= 3.50√21
= 150√21

Luas permukaan limas = Lalas +L selimut
= 100√3+ 150√21 cm²