Question

A point P (a, b) is reflected in the x-axis to P’ (2, -3), write down the values of a and b. P” is the image of P, when reflected in the y-axis. Write down the co-ordinates of P”. Find the co-ordinates of P”, when P is reflected in the line parallel to y-axis such that x = 4.

Answer 1

Given,

P’ (2, -3) is the reflection of P (a, b) in the x-axis

Hence, the co-ordinates of P’ will be (a, – b) but P’ is (2, -3)

On comparing, we get a = 2, b = 3

Thus, the co-ordinates of P will be (2, 3)

And,

P” is the image of P when reflected in y-axis

Hence, the co-ordinate of P” will be ( – 2, 3)

Now, draw a line x = 4, which is parallel to y-axis

As P’” is the image of P when it is reflected in the line x = 4,

So, P’” is its reflection.

Thus, the co-ordinates of P”’ will be (6, 3).