Mathematics
Points A and B have coordinates (2, 5) and (0, 3). Find :
(i) the image A' of A under reflection in the x-axis.
(ii) the image B' of B under reflection in the line AA'.
Answer
The graph with the points A (2, 5), B (0, 3) and their images A' and B' is shown below:
(i) We know that,
Rule to find reflection of a point in x-axis :
- Retain the abscissa i.e. x-coordinate.
- Change the sign of ordinate i.e. y-coordinate.
∴ Point A'(2, -5) is the image on reflection of A(2, 5) in x-axis.
The coordinates of A' are (2, -5).
(ii) From graph we get,
The coordinates of B' are (4, 3).
Related Questions
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 coordinates of P''. Find the coordinates of P''', when P is reflected in the line, parallel to y-axis such that x = 4.
(i) Point P(a, b) is reflected in the x-axis to P'(5, -2). Write down the values of a and b.
(ii) P'' is the image of P when reflected in the y-axis. Write down the coordinates of P''.
(iii) Name a single transformation that maps P' into P''.
The points (6, 2), (3, -1) and (-2, 4) are the vertices of a right angled triangle. Check whether it remains a right angled triangle after reflection in the y-axis.
Plot the points A(2, -3), B(-1, 2) and C(0, -2) on the graph paper. Draw the triangle formed by reflecting these points in the x-axis. Are the two triangles congruent ?