|AF|*h1 | |FC|*h1 | |BG|*h2 | |GC|*h2 | ||||
+ | + | + | =PΔABC | ||||
2 | 2 | 2 | 2 |
h1(|AF|+|FC|) | h2(|BG|+|GC|) | ||
+ | =PΔABC | ||
2 | 2 |
h1(|AF|+|FC|) | h2(|AF|+|FC|) | ||
+ | =PΔABC | ||
2 | 2 |
(|AF|+|FC|)(h1+h2) | |
=PΔABC | |
2 |
(|AF|+|FC|)(h1+h2) | |EB|*(|AF|+|FC|) | ||
= | |||
2 | 2 |
1 | 1 | |||
P(ABC)= | |BC|*h i P= | |AC|*h | ||
2 | 2 |
1 | 1 | |||
P(ABC)= | *x*|BC|+ | *y*|AC| i |AC|=|BC| | ||
2 | 2 |
1 | 1 | |||
to P(ABC)= | *|BC|(x+y) i P(ABC)= | |BC|*h ⇒ x+y=h | ||
2 | 2 |