Question

please help me asap
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Answer 1

Step-by-step explanation:

Finding Determinant

D = \begin{gathered} \left[\begin{array}{ccc}3&4&5\\2&-1&8\\5&-2&7\end{array}\right] \end{gathered}⎣⎢⎡3254−1−2587⎦⎥⎤

=3(-7+16)-4(14-40)+5(-4+5) = 136

Dx = \begin{gathered}\left[\begin{array}{ccc}18&4&5\\13&-1&8\\20&-2&7\end{array}\right]\end{gathered}⎣⎢⎡1813204−1−2587⎦⎥⎤

=18(-7+16)-4(91-160)+5(-26+20) = 408

Dy = \begin{gathered}\left[\begin{array}{ccc}3&18&5\\2&13&8\\5&20&7\end{array}\right] \end{gathered}⎣⎢⎡325181320587⎦⎥⎤

=3(91-160)-18(14-40)+5(40-65) = 136

Dz = \begin{gathered}\left[\begin{array}{ccc}3&4&18\\2&-1&13\\5&-2&20\end{array}\right]\end{gathered}⎣⎢⎡3254−1−2181320⎦⎥⎤

=3(-20+26)-4(40-65)+18(-4+5) = 136

Therefore x = Dx/D  = 408/136 = 3

y = Dy/D = 136/136 = 1

z= Dz/D = 136/136 = 1