<p><a href="http://www.sat-taiwan.com.tw/pdf/GettingReadyfortheSAT82425.pdf%5B/url%5D">http://www.sat-taiwan.com.tw/pdf/GettingReadyfortheSAT82425.pdf</a> This is the 2010-2011 official practice booklet. The problem I'm talking about is #4 on page 62 of the document.</p>
<p>I've seen this type of problem before, and it ALWAYS trips me up. What polygon are they asking you to measure? Are you supposed to leave out side AE of the square? please help</p>
<p>ABCDE is a reference to the entire figure. You are expected to measure side AE. </p>
<p>For example, when someone says look at triangle ABC - do you leave out side AC? No … then it wouldn’t be a triangle ;). </p>
<p>In any case, the answer is B. The perimeter of the figure is 5. </p>
<p>Here’s how to crack this problem:</p>
<p>1) Recognize given info and find the implied messages </p>
<p>ΔCDE is equilateral -> all its sides are equal in length
ABCE is a square -> all its sides are equal in length
the area of ABCE is 1 -> its length and width both = 1 as 1*1 = 1</p>
<p>2)** What is the problem? **</p>
<p>Problem: Find the perimeter of ABCDE
ETS trick: side CE is not part of the perimeter! *Don’t factor in the length of side CE! *</p>
<p>3) Solution:</p>
<p>a) Realize that all of the sides of ABCE have a length of 1. Add up the lengths of the exterior sides. 1 + 1 + 1 = 3.</p>
<p>b) Realize that side CE is also part of the equilateral triangle. Also realize that side CE has a length of 1. Now put this together and realize that each side of the triangle has a length of 1. Add up the exterior sides. 1 + 1 = 2.</p>
<p>c) Add 3 and 2 to get 5. </p>
<p>Solved.</p>
<p>Took less then 10 seconds to answer this.</p>
<p>Each side of the square = 1
Each side of the triangle = 1
ABCDE refers to the whole figure (remember this, when you have a reference to almost all the letters, it’s a reference to the whole figure)
1+1+1+1+1 = 5</p>
<p>Do not get into the mistake of counting that side which is shared by the triangle and square. C is not the answer.</p>
<p>All right I got it. These mid-level geometry problems are the bane of my SAT existence, I get hard and easy ones right, but the mediums throw me for a loop.
Thanks everybody</p>