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Given:

  • Circle with centre $M (-5; 5)$
  • The equation is $(x+5)^2 + (y-5)^2 = 50$

Suppose this figure is translated $6$ units to the right and $3$ units down. What is the new centre of the circle?

My attempt for the centre is $x + 6$ and $y - 3$, yielding $M (1; 2)$, but the answer in the textbook is $M (1; 5)$

Explain?

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  • $\begingroup$ Explain? Typo. 6 units to the right of -5 is 1. 3 units down from 5 is 2 so the center is (1,2). That's it. Unambiguous and inarguable. The book is wrong. I don't the book author is stupid so ... I must conclude it is an uncaught typo. $\endgroup$ – fleablood Mar 22 '16 at 17:15
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The equation implies the circle center at $(-5,5)$ indeed, which is your point $M$. Moving 6 right and 3 down should yield $$ (-5,5) + (6,-3) = (-5+6,5-3) = (1,2) $$

Could be a typo in the book?

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