Mirror!
Geometry
Level
2
Find the image of the point (3,8) with respect to the mirror x+3y=7
If your answer is (a,b), enter the answer as abs(a)+abs(b)
The answer is 5.
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1 solution
Slope of normal to the mirror is 3, and the normal through the point would be y − 8 = 3 × ( x − 3 ) . . . . > y = 3 x − 1
The normal and the mirror intersect at (1, 2). ..>
(1, 2) is the midpoint of the point and its image. thus the image is (- 1, - 4)
5