Perhatikan gambar berikut! nilai p adalah.
tolong dong huhu senin dikumpulin
tolong dong huhu senin dikumpulin
![](https://id-static.z-dn.net/files/d88/35b8424c01ec4819ee09e3bf826a42b8.jpg)
Jawab:
segitiga siku
pythagoras
Δ ADC siku di D
CD² = AC² - AD²
CD² = 13² - x² . . . (i)
Δ CDB siku di D
CD² = BC² - DB²
CD² = 20² - (21-x)² . .. (ii)
i = ii
13² - x² = 20² -(21 - x)²
169 - x² = 400 - (441 - 42 x+ x²)
169 - x² = 400 - 441 + 42 x- x²
169 - x² = - 41 + 42 x- x²
- x² + x² - 42x = - 41 - 169
-42x = - 210
x = 5
x= p = 5