Question

Point А (4, –1) is reflected as A' in the y-axis. Point B on reflection in the x-axis is mapped as B' (–2, 5). Write the co-ordinates of A' and B.

Answer 1

Reflection in y-axis is given by,

M_y(x, y) = (–x, y)

∴ Image on reflection of A(4, –1) in y-axis = A'(–4, –1).

Let B = (a, b)

Reflection in x-axis is given by,

M_x(x, y) = (x, –y)

∴ Image on reflection of B(a, b) in x-axis = B'(a, –b).

Given, B' = (–2, 5)

so, a = –2 and –b = 5

⇒ a = –2 and b = –5.

Hence, A' = (–4, –1) and B = (–2, –5).