CUBECUBE and CUBOIDCUBOID To calculate the sum of edges, length of face/plane diagonal, and diagonal, also area of diagonal plane Created by Cep Andi Alim Subarkah for mathlabsky.wordpress.com
The sum of Edge The length of face diagonal The length of diagonal The area of diagonal plane A B C D E H F G r cm EXAMPLE 1 EXAMPLE 2
A B C D E H F G r cm Look at ∆BAE, ∠ A is right angle. → → → → →
A B C D E H F G r cm Look at ∆CAE, ∠ A is right angle. → → → → →
A B C D E H F G r cm → → → Look at rectangle ABGH
Given a cube with measure of edge is 4 cm. calculate a.The sum of edgesc. The length of diagonal b.The length of face diagonald. The area of diagonal plane The answer: a. The sum of edges → 12 x r = 12 x 4cm = 48 cm
The answer: L.O.F.D r r r= 6 cm a. The sum of edges → 12 x r = 12 x 6cm = 72 cm
A B C D E H F G l cm w cm h cm The sum of Edge The length of face diagonal The length of diagonal Example 1 Example 2
A B C D E H F G l cm w cm h cm Look at ∆CBF, ∠ B is right angle. Look at ∆ABC, ∠ B is right angle.
A B C D E H F G l cm w cm h cm Look at ∆CAE, ∠ A is right angle. → → → →
The answer : a.The sum of edges : 4 (l + w + h) : 4 ( ) : 4 (25) : 100 cm A B C D E F G H 10 cm 6 cm 9 cm
A B C D E F G H 10 cm 6 cm 9 cm
Sebuah balok memiliki ukuran rusuk alas 8 cm x 10cm. Jika panjang seluruh rusuk balok adalah 92cm, maka panjang diagonal ruang balok adalah … Jawab Panjang rusuk Seluruh = 92 4 (p + l + t) = 92 4 ( t) = 92 4 (18 + t) = t = 92 : 4 = 23 t= 23 – 18 = 5