<p>It's #55 on the 2007 Barron's ACT book.
Here's the link:</p>
<p>Barron's</a> ACT, 2007-2008 - Google Books</p>
<p>It's on page 37.
I don't understand the answer nor the explanation.</p>
<p>Thanks.</p>
<p>It’s basically just similar triangles. Shift the inner right triangle and redraw it so that it matches the bigger right triangle. So DA (small triangle) is proportional to BA (big triangle) and AB (hypotenuse of small triangle) is proportional to AC (hypotenuse of big triangle). So this leads to 3/4 = 4/x and 3x = 16. So x = 16/3 which is E.</p>
<p>In my opinion, this question is badly formatted (Barron’s has some of these) and wouldn’t show up in a real ACT test.</p>
<p>I think I got it. Thanks.
And yeah, I am not that fond of Barron’s questions. A lot of them are phrased weird so I have to read them over and over again until I finally get them.</p>
<p>■■■■■ how is the question phrased “weirdly”? </p>
<p>Here’s the question: In the right triangle ABC, (angle B is the right angle), altitude BD is drawn. If AB= 4 and AD=3, what is the length of AC? </p>
<p>What is so weird about that?</p>
<p>Sounds more of an excuse than anything else.</p>
<p>^What’s wrong with an excuse? College is an excuse to wake up everyday.</p>
<p>^That was very pessimistic. I just woke up still tired from a nap. :(</p>
<p>^ You are the quintessential wild snorlax.</p>