Question

1)Gambar 1,besar sudut D adalah...
a.42'
b.62'
c.72'
d.82'

2)Gambar 2,jika sudut ABC = 130',maka besar sudut C adalah...
a.50'
b.45'
c.40'
d.32'

3)Gambar 3,besar sudut Q = 120' dan S = 60',maka Besar sudut P dan sudut R berturut-turut adalah...
a.70' dan 70'
b.70' dan 80'
c.90' dan 80'
d.90' dan 90'

4)Perhatikan gambar 4,besar sudut B adalah...
a.30'
b.40'
c.55'
d.60'

5)Perhatikan gmr 5,besar sudut R adalah...
a.30'
b.45'
c.65'
d.105'

Answer 1

Nomor 1.
<A + <D = 180°
108° + <D = 180°
<D = 180° - 108°
<D = 72° [C]

Nomor 2.
<ABC = <ADC = 130°
<BAD = <BCD
Maka,
<ABC+<ADC+<BAD+<BCD=360°
130° + 130° + <BCD + <BCD = 360°
2<BCD + 260° = 360°
2<BCD = 100°
<BCD = 50°
<C = 50° [A]

Nomor 3.
<P = <R
Maka,
<P + <Q + <R + <S = 360°
<P + 120° + <P + 60° = 360°
2<P + 180° = 360°
2<P = 180°
<P = 90°
Dan,
<R = 90°
PIlihan = D

Nomor 4.
<A + <B + <C = 180°
60° + <B + 80° = 180°
<B + 140° = 180°
<B = 40° [B]

Nomor 5.
Tentukan x.
<P + <Q + <R = 180°
3x + 7x + 2x = 180°
12x = 180°
x = 15°
Sehingga,
<R = 2x
<R = 2(15°)
<R = 30° [A]