Question

Which point is a reflection of point R(-2, 9) first across the y-axis and then across the x-axis?

A.(-9, -2)
B.(-2, -9)
C.2, -9)
D.(9, -2)

Answer 1

`\hbox{Given a point }A=(x,y) \hbox{, its the reflection }\\ \hbox{across the x-axis is: }A'=(x_A,-y_A)\\ \hbox{across the y-axis is: }A'=(-x_A,y_A)\\\\ \hbox{The reflection of }R \hbox{ across the x-axis is: }\\ R'=(-2,-9)\\ \hbox{The reflection of } R \hbox{ across the y-axis is: }\\ R'=(-(-2),9)=(2,9)`