Jawapan

2016-08-31T16:27:57+08:00
Pepnjuru =( (bilngan sisi - 3)× (bilngan bucu) ÷ 2
cth ppnjuru pentagon

( (5-3) × 5 ) ÷ 2
= (2×5) ÷ 2
= 10 ÷ 2
= 5

shortcut

( (4-3)×5)
--------------
2

= 5
1 4 1