besar sudut CBD adalah............

jawab
sudut luar segitiga
<CBD = 180 - 7x

9x = 92 + 180 - 7x
9x + 7x = 272
16x  - 272
x = 17

<CBD  = 180- 7x = 180 - 7(17) = 61

180-7x = 9x - 92
180+92=9x+7x
272 = 16x
x = 272/16 = 17

Sudut CBD = 180 - 7x
= 180 - 7(17)
= 180 - 119
= 61 derajat.