Tolong dong, pake cara jga yaa~!!
Jawab:
11.
a.) x = 14
b.) <KNM = 106°, <MNL = 74°
12.
a.) y = 34
b.) <ABE = 87°, <DBC = 59°
13. x = 12 (D)
14.
a.) x = 22
b.) y = 10
15.
a.) a = 17
b.) b = 23
c.) c = 113
Penjelasan:
11.
a.) <KNM + <MNL = 180
(7x + 8) + (5x + 4) = 180
7x + 8 + 5x + 4 = 180
7x + 5x + 8 + 4 = 180
12x + 12 = 180
12x + 12 – 12 = 180 – 12
12x = 168
12x/12 = 168/12
x = 14
b.) <KNM = 7x + 8
<KNM = 7(14) + 8
<KNM = 98 + 8
<KNM = 106°
<MNL = 5x + 4
<MNL = 5(14) + 4
<MNL = 70 + 4
<MNL = 74°
12.
a.) (3y – 15) + y + (2y – 9) = 180
3y – 15 + y + 2y – 9 = 180
3y + y + 2y – 15 – 9 = 180
6y – 24 = 180
6y – 24 + 24 = 180 + 24
6y = 204
6y/6 = 204/6
y = 34
b.) <ABE = 3y – 15
<ABE = 3(34) – 15
<ABE = 102 – 15
<ABE = 87°
<CBD = 2y – 9
<CBD = 2(34) – 9
<CBD = 68 – 9
<CBD = 59°
13. (4x + 9) + 33 = 90
4x + 9 + 33 = 90
4x + 42 = 90
4x + 42 – 42 = 90
4x = 90
4x/4 = 90/4
x = 12
14.
a.) 6x = 132
6x/6 = 132/6
x = 22
b.) 4y + 8 = 180 – 132
4y + 8 = 48
4y = 48 – 8
4y = 40
4y/4 = 40/4
y = 10
15.
a.) 8a = 136
8a/8 = 136/8
a = 17°
b.) b = 180 – 157
b = 23°
c.) c = 180 – (180 – 136) – b
c = 180 – 44 – 23
c = 180 – 44 – 23
c = 113°