Engineering Board Exam Reviewer · Conic Sections and Transformation of Axes · medium
The coordinate axes are rotated counterclockwise through 90°. What are the new coordinates of the point (3,4)?
- (-4,3)
- (4,-3)
- (3,-4)
- (-3,4)
Answer
B. (4,-3)
Solution
x'=x +y =4 and y'=-x +y =-3 for =90°.
More Conic Sections and Transformation of Axes questions
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