Question

A point P(−7, 8) is first reflected in the origin and then in x-axis to get the point Q. The co-ordinates of point Q are ______.

Options

• (−7, 8)

• (7, 8)

• (7, −8)

• (−7, −8)

Answer 1

A point P(−7, 8) is first reflected in the origin and then in x-axis to get the point Q. The co-ordinates of point Q are (7, 8).

Explanation:

We know that,

On reflecting in origin the sign of both x and y co-ordinate changes.

Let on reflection in origin P(−7, 8) becomes P'.

P(−7, 8) = P'(7, −8)

We know that,

On reflecting in x-axis the sign of y co-ordinate changes.

According to question,

On reflection in x-axis P'(7, 8) becomes Q.

P'(7, −8) = Q(7, 8).