Page 57 - Digital Book Bangun Datar Segitiga Kelas VII

No. Kunci Jawaban

Langkah 1: Langkah 2:

Karena jumlah sudut 180° maka: = 25 disubtitusikan ke:

 +  +  = 180⁰  = 4 + 5

30 + (4 + 15) + ( + 10) = 180° = 4(25) + 15

3. (5 + 55) = 180° = 100 + 15 = 115°

5 = 180 − 55
5 = 125  = + 10

= 125 ∶ 5 = 25 + 10

= 25 = 35°

Untuk mencari nilai lihat sudut

luar segitiga = 120° karena
berpelurus.

 =  +
2
2
120° = 56 +
120 − 56 =

4. 64 =
Nilai

 +  +  = 180°
2
+ + 120° = 180°

2 = 180° − 120°
2 = 60°

= 30°

 =  +  +  = 180⁰

= 50 + 75 +  = 180⁰

= 125 +  = 180⁰

 = 180 − 125
5. = °

 =  + 

= 50 + 75 = °

Digital Book Matematika SMP/MTs kelas VII
51