Question

Matemática urgente ajuda

Answer 1

Resposta:

Letra C.

Explicação passo-a-passo:

$A=\left[\begin{array}{cc}3&1\\1&-2\\\end{array}\right]$

$B=\left[\begin{array}{cc}x+y&x-y\\1&-2\end{array}\right] \ \therefore\ B^t=\left[\begin{array}{cc}x+y&1\\x-y&-2\end{array}\right]$

$A=B^t\ \therefore\ \left[\begin{array}{cc}3&1\\1&-2\end{array}\right] =\left[\begin{array}{cc}x+y&1\\x-y&-2\end{array}\right]\ \therefore$

$\begin{center} \left\{\begin{array}{cc}x+y=3\\x-y=1\end{array}\right$

$x+y+x-y=3+1\ \therefore\ 2x=4\ \therefore\ \boxed{x=2}\\\\ x+y=3\ \therefore\ 2+y=3\ \therefore\ \boxed{y=1}$