Diketahui keliling segitiga ABC= 75cm. Panjang sisi AB= 25cm dan sisi BC= 20cm. Tentukan luas segitiga ABC

Dik:
=> K(ABC) = 75cm
=> AB = 25cm
=> BC = 20cm
Dit: L(ABC) = ?
Jwb:
=> AC = K-(AB+BC) = 75-(25+20) = 75-45= 30cm
=> L(ABC) = 1/2(a×t)
=> L(ABC) = 1/2(AC×t)
Mencari tinggi: t = akar(AB^2-(1/2AC)^2)
============> t = akar(25^2-(1/2×30)^2)
============> t = akar(625-15^2) = akar(625-225) = akar(400) = 20cm

Maka, L(ABC) = 1/2(AC×t) = 1/2(30×20) = 1/2(600) = 300cm2

Maaf kalau salah yaa... ^^