<p>Blue book, page 522.</p>
<p>In the xy-plane, line l passes through the origin and is perpendicular to the line 4x+y=k, where k is a constant. If the two lines intersect at the point (t,t+1), what is the value of t?</p>
<p>(A) -4/3
(B) -5/4
(C) 3/4
(D) 5/4
(E) 4/3</p>
<p>Thanks in advance!</p>
<p>Hint: find the slope of the given line, and use the fact that the slopes of two perpendicular lines satisfy m1 * m2 = -1 ...</p>
<p>Another hint: if all else fails, read the manual (<a href="http://talk.collegeconfidential.com/sat-preparation/339734-consolidated-list-blue-book-math-solutions-3rd-ed.html%5B/url%5D">http://talk.collegeconfidential.com/sat-preparation/339734-consolidated-list-blue-book-math-solutions-3rd-ed.html</a>).</p>
<p>Ah. Thanks. I got it after fignewton's hint. =)
Gcf101, that link is great!! It's helped me more than you can imagine.</p>
<p>^Thanks, blue_box! I too think this List is an amazing resource. With so many people contributing their solutions you can always find one that suits your style best - be it visual, or "plug'n'chug", or magic "xiggi's formula". In that sense this compendium beats hands down the College Board (the explanations are in its online course) along with Test Masters and other sources.
And it keeps growing! Maybe College Confidential should publish it and acquire the copyrights?</p>
<p>The Collegeboard's guide is extremely disappointing. I think it's aimed at those who already have a basic idea of the topics tested in the SAT.. I didn't understand much about functions, probably the only topic that I still don't get.
CC should definitely publish the trove of info on these boards. Though, personally I feel an online CC course would be much more practical and helpful. One that can be edited and upgraded by CC members (like Wikipedia) but can still charge subscription. Since CC doesn't have any paid workers, a Wikipedia-styled book is the best option.</p>
<p>Your idea of CiCipedia is very interesting. If only somebody found time and energy to start this undertaking! One possible obstacle - the College Board copyrights on its questions. There must be a way though to resolve that.
Actually, this topic is very getable.
I think most of the questions on functions are answered in a similar fashion.
All you need to know that if you are given a formula (or defined operation) for f(x) (see 461/10, 684/16, 779/18), or f(a,b) (see 412/16, 463/17, 587/20), or even f(x,y,z) (see 778/11), you just plug the numbers or expressions in place of corresponding variables and perform prescribed manipulations (like squaring, adding, and the such).
Graphs might be a little bit more difficult, but once you get a hang of them you'll be cracking questions on them in no time.
You really need to make these concepts clear for yourself because each and every SAT test includes the whole bunch of related questions. You'll feel so excited when you encounter any of them on the test: 10 points for very little effort!</p>
<p>I can do calculations with functions. It's the graphs I have problems in. And the worst part is there are a truckload of graph questions in every SAT test, and my SAT is tomorrow. That sucks.</p>