<p>In the figure above, ABCD is a rectangle with BC=4 and AB=6. Points P,Q, and R are different points on a line(not shown) that is parallel to AD. Points P and Q are symmetric about line AB and points Q and R are symmetric about line CD. What is the length of PR?</p>
<p>If you have the bluebook, you can flip to the #12 section 9, Practice test #2 or just page 490.</p>
<p>Thanks!</p>
<p>Do you have the answer choices?</p>
<p>B: 8</p>
<p>Answer choices are:
A) 6
B) 8
C) 10
D) 12
E) 20</p>
<p>8.
Pq=2; Qr=6
2+6=8</p>
<p>Actually, no matter what value you choose the result is always 8.
For example: PQ=4, so then QR=4. 4+4 still equals 8.
As long as PQ/2+QR/2=8 it will work. That is a given must.</p>
<p>By the way, in case anyone is wondering, symmetrical means that the segment is bisected.</p>
<p>See the stickied</a> thread for more explanations</p>
<p>Thank you so much!</p>
<p>sorry, I don't get this. I understand that symmetric about means it's bisecting the line. so wouldn't that be bisecting line ab which means it would be 6/2 = 3? so 3+3 =6?</p>
<p>Well, symmetric about the line means that it's equidistant from it, so...</p>
<hr>
<p>|__|
. .
P Q</p>
<p>where AB is the line most to the left (I haven't seen the diagram so I don't know how it actually is.)</p>
<p>Here, imagine that u extend AB so you have</p>
<hr>
<p>|__|
. | .<br>
P Q</p>
<p>the distance from Q to the extension of AB = distance from P to extension of AB (and since a line is infinite, the extension of AB is the line AB).</p>
<p>Now imagine extending CD too.</p>
<hr>
<p>|___|
. | . | .
P Q R</p>
<p>Q to the extension of CD = R to the extension of CD, thus Q and R are equidistant from CD.</p>
<p>Now to get PQR, notice how (Q to AB) + (Q to CD) = 4 (length of BC, given).
Similarly, if (P to AB) = (Q to AB) and (R to CD) = (Q to CD), replace it in the equation above to get (P to AB) + (R to CD) = 4 too.</p>
<p>SO in total, (P to AB) + (Q to AB) + (Q to CD) + (R to CD) = P to R = 4 + 4 = 8.</p>
<p>Hope that helps.</p>
<p>To the OP--no, because it's not the side of the shape that is being bisected--it's that other segment that crosses with the side.</p>
<p>Good god, all the answers of the blue book are online at collegeboard.com</p>
<p>What do you mean jason15975346?
Do you mean the Online Course?</p>
<p>metaldemon, that really helps! Thanks a lot!! :D</p>
<p>When you logon to collegeboard.com click the official book and its got all the answers.</p>
<p>does it also have explanations?</p>
<p>YES! Why would I tell you if it didn't have explinations.</p>
<p>Only the Online Course contains explanations for the Official Guide to SAT.</p>
<p>Meh, if you have resources (google) the online course is free. Heh.</p>
<p>Jason15975346, are you implying that I steal the Online Course codes?</p>