Question

Dado o triângulo cujos vértices são A(1,1), B(4,0) e C(3,4), a área do triângulo ABC é:

Answer 1

$\huge\mathtt{M=\begin{bmatrix}1&1&1\\4&0&1\\3&4&1\end{bmatrix}}$

$\mathtt{det~M=1(-4)-1(4-3)+1(16)}\\\mathtt{det~M=-4-1+16}\\\mathtt{det~M=11}$

$\mathtt{A=\dfrac{1}{2}|M|}\\\mathtt{A=\dfrac{1}{2}.11}$

$\boxed{\boxed{\mathtt{M=\dfrac{11}{2}~u.a}}}$