Question 165755
<pre><font size = 4 color = "indigo"><b>
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Given: PQ <font face = "symbol">@</font> PS; QR <font face = "symbol">@</font> SR
        <font face = "symbol">Ð</font>1 <font face = "symbol">@</font> <font face = "symbol">Ð</font>2
 Prove: <font face = "symbol">Ð</font>3 <font face = "symbol">@</font> <font face = "symbol">Ð</font>4  

{{{drawing(400,240,-3,9,-3,3,
triangle(-2,0,7.833,0,0,2.3835),
triangle(-2,0,7.833,0,0,-2.3835),
locate(-1.6,.4,1), locate(-1.6,-.08,2),
locate(6.3,.4,3),locate(6.3,-.06,4),
locate(-2.3,.3,P),locate(8,.3,R),
locate(-.1,2.9,Q),locate(-.1,-2.4,S)
 )}}}

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PQ <font face = "symbol">@</font> PS          Given

<font face = "symbol">Ð</font>1 <font face ="symbol">@</font> <font face = "symbol">Ð</font>2         Given
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PR <font face ="symbol">@</font> PR         A line segment is congruent
                to itself.  (Identity)

<font face = "symbol">D</font>PQR <font face = "symbol">@</font> <font face = "symbol">D</font>PSR     Side-Angle-Side

<font face = "symbol">Ð</font>3 <font face ="symbol">@</font> <font face = "symbol">Ð</font>4         Corresponding parts of congruent triangles.


Notice that you did not need to be given that 
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QR <font face = "symbol">@</font> SR, for it was not used.


Edwin</pre>