C-11-Q055mediumsingle_mcqশীর্ষ A(x1,y1),B(x2,y2),C(x3,y3)A(x_1, y_1), B(x_2, y_2), C(x_3, y_3)A(x1,y1),B(x2,y2),C(x3,y3) ত্রিভুজের ক্ষেত্রফল—a12∣x1(y2−y3)+x2(y3−y1)+x3(y1−y2)∣\dfrac{1}{2}|x_1(y_2-y_3) + x_2(y_3-y_1) + x_3(y_1-y_2)|21∣x