Answer with explanation:
(a)→Coordinates of Vertices of triangle = (-2,-3), (3,5) and (8, -1).
Plotting these points in two dimensional coordinate plane:
Now when the points are reflected through X axis, the distance of points from line , y=0, on both sides is same .That is distance of Preimage from ,line, y=0 is same as Distance of Image from the line.
≡Rule of reflection of (x,y)→ (x, -y).
⇒Coordinates of Image =(-2,3), (3, -5), (8,1).
In Matrix form
![\left[\begin{array}{ccc}-2&-3\\3&5\\8&-1\end{array}\right] \text {reflected across X axis}=\left[\begin{array}{ccc}-2&3\\3&-5\\8&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%26-3%5C%5C3%265%5C%5C8%26-1%5Cend%7Barray%7D%5Cright%5D%20%5Ctext%20%7Breflected%20across%20X%20axis%7D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%263%5C%5C3%26-5%5C%5C8%261%5Cend%7Barray%7D%5Cright%5D)
(b) → Coordinates of Vertices of triangle = (-2,-3), (3,5) and (8, -1) is rotated by 90 degree, the vertices of triangle will be , (-3, 2), (5, -3), (-1, -8).
The rule is , after 90 degree rotation . point (a,b)→(b, -a).
Plotting these points in two dimensional coordinate plane:
In Matrix form
![\left[\begin{array}{ccc}-2&-3\\3&5\\8&-1\end{array}\right] \text {reflected across X axis}=\left[\begin{array}{ccc}-3&2\\5&-3\\-1&-8\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%26-3%5C%5C3%265%5C%5C8%26-1%5Cend%7Barray%7D%5Cright%5D%20%5Ctext%20%7Breflected%20across%20X%20axis%7D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-3%262%5C%5C5%26-3%5C%5C-1%26-8%5Cend%7Barray%7D%5Cright%5D)