Question

Reflect the given triangle over
the line y=x.

[3 6 3
-3 3 3]

Answer 1

[3,-3,-3] [-3,-6,3]

Explanation:

jus got it right

Answer 2

If reflected over y = x

then use

`\left[\begin{array}{ccc}0&1\\1&0\end{array}\right]`

=====================

`\left[\begin{array}{ccc}0&1\\1&0\end{array}\right] \left[\begin{array}{ccc}3&6&3\\-3&3&3\end{array}\right]`

similar as (x, y) → (y, x)

multiply the matrixes to get the final answer

`\left[\begin{array}{ccc}(3*0+1*-3)&(6*0+1*3)&(3*0+1*3)\\(3*1+(-3*0)&(1*6+0*3)&(1*3+0*3)\end{array}\right]`

`\left[\begin{array}{ccc}-3&3&3\\3&6&3\end{array}\right]`