Difference between revisions of "Power of a Point Theorem/Introductory Problem 1"

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== Solution ==
 
== Solution ==
  
Applying the Power of a Point Theorem gives us <math> 3\cdot(3+5) = x (x+10) </math>.  Expanding and simplifying we get <math> x^2 + 10x - 24 = 0 </math>.  This factors as <math> (x+12)(x-2) = 0 </math>  We discard the negative solution since distance must be positive.  Thus <math> x=2 </math>.
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Applying the Power of a Point Theorem gives us <math> 3\cdot(3+5) = x (x+10) </math>.  Expanding and simplifying we get <math> x^2 + 10x - 24 = 0 </math>.  This factors as <math> (x+12)(x-2) = 0 </math>. We discard the negative solution since distance must be positive.  Thus <math> x=2 </math>.
  
 
''Back to the [[Power of a Point Theorem]].''
 
''Back to the [[Power of a Point Theorem]].''

Revision as of 13:38, 3 July 2006

Problem

Find the value of $x$ in the following diagram:

Popprob1.PNG

Solution

Applying the Power of a Point Theorem gives us $3\cdot(3+5) = x (x+10)$. Expanding and simplifying we get $x^2 + 10x - 24 = 0$. This factors as $(x+12)(x-2) = 0$. We discard the negative solution since distance must be positive. Thus $x=2$.

Back to the Power of a Point Theorem.