Jawabanmu

2014-06-02T19:31:18+07:00
T = √13² - 5²
= √169 - 25 = √ 144 = 12 cm
L = 15 + 25 /2 .12 = 40 . 6 = 240 cm² 
2014-06-02T19:31:54+07:00
15cm+25cm/2 ×13cm
=40/2 ×13cm
=20×13
=260㎠