Question

i. determine the coordinates of vertex a after it has been rotated 90° clockwise about the origin and then reflected over the y - axis.
ii. plot triangle abc in the graph, rotated 90 degrees cw, centered at (0, 0) and triangle abc, the reflection of triangle abc over the y - axis.
a(2, 10)
b(2, 2) c(8, 2)
a(-10,-2)
a(10,2)
a(-10,2)
a(10,-2)

Explanation:

Step1: Apply 90 - degree clockwise rotation formula

The formula for a 90 - degree clockwise rotation about the origin is $(x,y)\to(y, - x)$. For point $A(2,10)$, after 90 - degree clockwise rotation, $A'=(10,-2)$.

Step2: Apply y - axis reflection formula

The formula for reflecting a point $(x,y)$ over the y - axis is $(x,y)\to(-x,y)$. For point $A'(10,-2)$, after reflection over the y - axis, $A''=(-10,-2)$.

Answer:

A. $A''(-10,-2)$