20 Points 20 points 20 points

Mathematics

2 answers:

Marat540 [252]3 years ago

6 0

Answer:

Step-by-step explanation:

$A=\left[\begin{array}{ccc}a&b\\c&d\end{array}\right] \\\\\det A=\left|\begin{array}{ccc}a&b\\c&d\end{array}\right|=ad-bc$

$\left\{\begin{array}{ccc}x+2y=5\\x-3y=7\end{array}\right\\\\A=\left[\begin{array}{ccc}1&2\\1&-3\end{array}\right] \\\\\det A=A=\left|\begin{array}{ccc}1&2\\1&-3\end{array}\right|=(1)(-3)-(1)(2)=-3-2=-5$

kykrilka [37]3 years ago

5 0

Answer:

-5

Step-by-step explanation:

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