I had a question about problem 6 on Diagnostic Drill #2 in your math book.
for IRREGULAR shapes, can you not use solely the triangle method (number of triangles x 180 degrees) to get the total interior angles? You seem to have subtracted 360 from the total number of degrees, 1080
In the figure above, line l is tangent to the circle at point P, and O is the center of the circle. What is the value of y?
A)50
B)55
C)60
D)65
E)75
what is the greatest possible area of triangle with the length of one side is 7 and another leg length is 10
The answer is 35
If points (6,0), (0,0), (0,2), and (a,2) are consecutive vertices of a trapezoid of area 7.5, what is the value of a?
A) 1.5
B) 2
C) 2.5
D) 5
E) 9
In figure 2, AB=BC. If the area of triangle ABE is x, what is the area of triangle ACD?
A) x sqrt2
B) x sqrt3
C) 2x
D) 3x
E) 4x
College Board released a bunch of sample questions this week for the new PSAT and SAT, which will make their debuts in October 2015 and March 2016, respectively. Over the next few days, I’ll be making posts working through each question, a few at a time, and commenting on them when I feel like I have (more…)
College Board released a bunch of sample questions this week for the new PSAT and SAT, which will make their debuts in October 2015 and March 2016, respectively. Over the next few days, I’ll be making posts working through each question, a few at a time, and commenting on them when I feel like I have (more…)
How’s everyone else doing on this quiz?
I was just noodling around with Geometer’s Sketchpad today, you know—like a totally normal person, and I made this figure, which I thought would make an awesome challenge question. Wasn’t even planning to post a challenge question, and then BAM! Inspiration. In the figure above, equilateral triangle DEF is partially obscured by a semicircle with (more…)
Yesterday I went to a museum and waited in line for a very long time for my turn to spend 5 minutes staring at a piece of art that completely mystified me. I guess it’s good art if I’m still thinking about it a day later, even if the thoughts I’m having mostly revolve around (more…)
This morning I was lying in bed waiting for my alarm to go off, and a question just popped into my head. This happens to me fairly often, but usually I’m too lazy to write it down, then I forget it, then I spend the rest of the day trying to convince myself that it (more…)
You know, It’s funny. When I sit down to write one of these, I usually have a rough sketch in my mind of how the question’s going to go. But half the time, the problem completely evolves into something else by the time I’m done with it. I’m not sure why that is. It could (more…)
Since you guys tore up my last challenge question so quickly, I figured I’d make this one a tiny bit harder. Let’s see if I can’t stump you for more than 8 minutes. First correct response in the comments gets a free Math Guide. Usual contest rules apply. Ready? Here we go! In the figure (more…)
Robin Hill Park (Jon Forster) / CC BY-SA 2.0 What an annoying weekend I had. It’s all my own poor planning, but the Math Guide went temporarily out of stock this weekend. Hopefully, everything will be back to normal by tomorrow, which means I can get right back to giving books away! This weekend challenge (more…)
Have you seen this movie? I liked it. Nobody’s answered the last challenge question yet, but whatever, here’s another one. And I’ll tell you what: First person who gets this one right gets a free Math Guide. Norville has four different colored hula hoops around his waist, each with a diameter of 3 feet. He (more…)
