Mohon dijawaban pertanyaan saya ya

Bab Garis dan Sudut
Matematika SMP Kelas VII

saya kerjakan nomor 1, 4, 5
karena nomor 2 dan 3 harus menggunakan alat

1a]
15° 27' 34"
74° 29' 43"
---------------- +
89° 56' 77"

77" = 60" + 17" → 1' 17"

89° 56' 77" = 89° 57' 17"

1b]
53° 28' 17"
42° 16' 33"
---------------- -
pinjam

53° 27' 77"
42° 16' 33"
---------------- -
11° 11' 44"


4] 1 putaran penuh = 360°
4a] 1/3 x 360° = 120° (sudut tumpul)

4b] 1/4 x 360° = 90° (sudut siku-siku)

4c] 1/9 x 360° = 40° (sudut lancip)


5] 4a + 60° + a = 180°
5a = 180° - 60°
a = 120° / 5
a = 24°

1. A
15° 27' 34"
74° 29' 43"
-------------- +
89° 56' 77" = 89° 57' 17"

1. B
53° 28' 17"
42° 16' 33"
-------------- -
11° 11' 44"

4. A
1/3 x 360°= 120° (<Tumpul)
4. B
1/4 x 360°= 90° (<Siku-siku)
4. C
1/9 x 360°= 40° (<Lancip)

5.
180° = (4a+60+a)°
180° = 5a° + 60°
120° = 5a°
24° = a