2021 AMC 12B Problems/Problem 5: Difference between revisions
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The | ==Problem== | ||
The point <math>P(a,b)</math> in the <math>xy</math>-plane is first rotated counterclockwise by <math>90\deg</math> around the point <math>(1,5)</math> and then reflected about the line <math>y = -x</math>. The image of <math>P</math> after these two transformations is at <math>(-6,3)</math>. What is <math>b - a ?</math> | |||
<math>\textbf{(A)} ~1 \qquad\textbf{(B)} ~3 \qquad\textbf{(C)} ~5 \qquad\textbf{(D)} ~7 \qquad\textbf{(E)} ~9</math> | |||
==Solution== | |||
<math>\boxed{\textbf{(D)} ~7}</math> | |||
Revision as of 17:41, 11 February 2021
Problem
The point 
in the 
-plane is first rotated counterclockwise by 
around the point 
and then reflected about the line 
. The image of 
after these two transformations is at 
. What is 
Solution
