Question

find the inverse of the matrix 3 -1 if it exists
-10 9

Answer 1

invese of \[\begin{matrix}
a & b \\
c & d
\end{matrix}\]
is \[\begin{matrix}
d & -b \\
-c & a
\end{matrix}\]
divided by the determinant
let me see if i can write it better

Answer 2

\[\frac{1}{ad-bc}\begin{pmatrix}
d & -b \\
-c & a
\end{pmatrix}\]

Answer 3

that thing out front means divide by the determinant

Answer 4

is it 9/17 1/17 ???
10/17 3/17

Answer 5

@satellite73

Answer 6

hold on let me check

Answer 7

yup

Answer 8

not too hard, was it?