http://sat.collegeboard.org/practice/sat-question-of-the-day?src=R&questionId=20130308 (This link takes you to today’s question. If you use my archive, you will see the question related to my SAT explanation for that date.)
This math concept became very popular starting in 2005 when the SAT underwent its last major revision. They recently announced a new major revision is coming. They didn’t announce a timeline but these things usually take 2-4 years.
The answer is B. When you see a question about the slope of two lines on the coordinate grid (xy-plane) that are perpendicular to one another, a little bell needs to ring in your head! That bell needs to sound like “negative reciprocal!” That is because the slopes of the two lines have to be the negative reciprocal of one another. All you have to do is calculate the slope of the first line and then convert it to the negative reciprocal and you’ll have the slope of the second line.
Determining the negative reciprocal is easy. First, change the sign of the slope from positive to negative or negative to positive depending on the slope of the first line. In this example, line l has a positive slope (rise/run); so, line m has to have a negative slope.
Second, determine its slope. Line l goes up (rise) 5 units from y=0 to y= 5. It goes over 2 units from x=0 to x=2 (run). That makes its slope 5/2. Now just invert (flip) the slope of 5/2 and you have 2/5. That makes the answer -2/5.
These are easy, very quick points. Just watch for the key words slope and perpendicular and you’ll know exactly what to do and the math is simple.
Let’s see if the ACT folks are this nice to us this morning!
http://www.act.org/qotd/ (The ACT staff does not put a date on their questions so if you click on an archived blog, you’ll get today’s question and the old explanation. Sorry. The SAT staff has dated their questions; so, the archive is helpful. The ACT folks simply don’t do that.)-
I’m sure getting tired of the ACT staff using the same questions over and over. This one appeared within the last week. I guess its time to make that YouTube video that my classes have recommended.
The answer is J. “Cumbrous swearing in very exact form proceeded without a mistake…” tells us that the swearing was detailed and required being exact or precise. None of the words have that meaning other than burdensome, answer J.
Enjoy your weekend.
The Wizard
