[Maths]
Question in Attachment.
Topic: Reflection (Coordinate Geometry)
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Answers
Topic :-
Coordinate Geometry
Question :-
P and Q have coordinates (0, 5) and (-2, 4).
(a) P is invariant when reflected in an axis. Name the axis.
(b) Find the image of Q on reflection in the axis found in (a).
(c) (0, k) on reflection in the origin is invariant. Write the value of k.
(d) Write the co-ordinates of the image of Q, obtained by reflecting it in the origin follówed by reflection in X-axis.
Solution :-
(a) Point P (0, 5) lies on Y-axis. Hence, when point P will be reflected in Y-axis then point P will be invariant.
(b) When any point (a, b) is reflected in Y-axis then coordinates of its image formed is (-a, b).
Thus, coordinates of image of point Q (-2, 4) after reflection in Y-axis will be (2, 4).
(c) When any point (a, b) is reflected in origin then coordinates of its image formed is (-a, -b).
Reflection of (0, k) in origin will be (0, -k).
It is given that, reflection of point (0, k) in origin is invariant which means x coordinate and y coordinate remains same after reflection.
Thus,
k = -k
k + k = 0
2k = 0
k = 0
So, the value of k is 0.
(d) It is given that point Q (-2, 4) is reflected in origin first, which means coordinates of its image formed will be (2, -4) as when any point (a, b) is reflected in origin then coordinates of its image formed is (-a, -b).
Finally, image (2, -4) is reflected in X-axis. When any point (a, b) is reflected in X-axis then coordinates of its image formed is (a, -b).
Thus, coordinates of image of point (2, -4) when reflected in X-axis will be (2, 4).
Answer :-
(a) Y-axis
(b) (2, 4)
(c) 0
(d) (2, 4)
HERE IS UR ANSWER
- y axis
- (2,4)
- k=0
- (2,4)