Question

If polygon MAST with coordinates M(-3,-1), A(-3,2),S (-1,3) and t (1,1) is reflected across x=-3, then which of the following coordinates represent the vertices of the polygon MAN'S'?

Answer 1

Answer:

The right choices are (-3,-1) ; (-3,2) ; (-5,3) ; (-7,1)

Step-by-step explanation:

MAST has coordinates M(-3,-1) ; A(-3,2) ; S (-1,3) ; T(1,1).

The mapping for reflection across the line  x = k is  

(x,y) -> ( 2k – x,y)

The coordinates of M'A'S'T'.

M'(2(-3)--3,-1) ;  A'(2(-3)--3,2) ; S' (2(-3)--1,3) ; T'(2(-3)-1,1)

M'(-6+3,-1) ; A'(-6+3,2) ; S' (-6+1,3) ; T'(-6-1,1)

M'(-3,-1) ; A'(-3,2) ; S' (-5,3) ; T'(-7,1)