Mathematics
(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''.
Answer
(i) Since, P'(5, -2) is the image of P under reflection in the x-axis, from graph P(5, 2).
∴ The coordinates of P are (5,2), comparing with P(a, b) we get, a = 5 and b = 2.
Hence, the value of a = 5 and b = 2.
(ii) We know that,
Rule to find reflection of a point in y-axis :
- Change the sign of abscissa i.e. x-coordinate.
- Retain the ordinate i.e. y-coordinate.
Since, P'' is image on reflection of P(5, 2) in y-axis.
Hence, the coordinates of P'' are (-5, 2).
(iii) The single transformation that maps P'(5, -2) into P''(-5, 2) is reflection in the origin.
Related Questions
If P'(-4, -3) is the image of a point P under reflection in the origin, find
(i) the coordinates of P.
(ii) the coordinates of the image of P under reflection in the line y = -2.
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 ?
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'.
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.