Official Act Math Thread June 2013

<p>ya jay i cant remember i put d or e i think</p>

<p>Was the set problem #59</p>

<p>We seem to be debating the one about m+n or mn and the question about the height of a point on a wheel the most. </p>

<p>For the one about m and n polynomials, mn is correct. You can verify it with equations such as (x^5+x^3+x)(x^2+x) and you get 6 terms. </p>

<p>For the one about the wheel, it is definitely like a sin graph. Just because the velocity of the point stays constant, it does NOT mean that the velocity in the x and y directions stay constant. For example, coming down on a ferris wheel, you are slowly moving faster in the - y direction and then slowing down; once you get to the bottom, you are slowing moving faster in the + y direction. The combined velocity of the x and y directions are the same, but at different points on the graph, the change in height will be different.</p>

<p>jay it was something like {x|-2<=x<4} or something like that. It was either d or e</p>

<p>d was like 6,8,10 and e was 8,12,17 i think and asked about which one was obtuse. i put d 6 8 10</p>

<p>The one with a diameter and a chord of 10 I think radius of 7. What did you guys get as the distance between the two? Answer choices were 4radical6 2radical6 5 and 4 maybe? Not sure? What’d y’all get?</p>

<p>@superduck </p>

<p>yes that was correct it was all the numbers between -2 and 4</p>

<p>@snayyan</p>

<p>It was 8, 11, 16 I belive</p>

<p>You can solve that with </p>

<p>a^2 + b^2 > c^2 means its obtuse and that was the only answer choice that satisfied that condition</p>

<p>I put 8, 11, and 16. I didn’t think of doing what @imadropout did t, but I just figured that since 16 and 11 had the largest difference of any of the answers, then it must be that.</p>

<p>@sideburns </p>

<p>yes it was 2sqrt6 because if 14 was the diameter, 7 is the radius and that was the diagonal/hypotenuse of a triangle. 10 was the lenght of the cord so 5 was the length of a side of the triangle. </p>

<p>so you get 7^2-5^2=24 -> sqrt24 = 2sqrt6</p>

<p>What did you guys get for the one that said A is 5 greater than B and B is 3 greater than C. Here’s what I did: A=B+5, and B=C+3. Substituting C+3 to the first equation, you get A>=C+8. I could’ve misread the problem, so I’m not completely sure.</p>

<p>I believe that it was A > c-2. </p>

<p>For the one that had it go from 2 to 3 inches deep, I put 17.</p>

<p>@debater</p>

<p>this is the rule for how you determine acute and right and obtuse triangles</p>

<p>a^2 + b^2 < c^2 actue
a^2 + b^2 > c^2 obtuse
a^2 +b^2 = c^2 right triangle</p>

<p>How do we determine which side is a, b, and c. </p>

<p>Also, if we did writing, is it still possible that we get our MC scores online on the 24th, or do we always have to wait the 5 weeks?</p>

<p>Would REALLY appreciate it if someone helped me out here.</p>

<p>For the 8, 11, 16 the obtuse triangle question, was that answer at the end of the choices or somewhat near the end?</p>

<p>Also, on one of the answer choices, was there an answer like x, y, 13? </p>

<p>I Just remember i picked the one with the greatest number that has greatest deviation from the 2nd greatest which was 5. (That corresponds to 8, 11, 16) But for some reason I remember a 13.</p>

<p>ahhhhhhhh i knew i should have changed it but whatever. 1/2 is right. 2.3 is right
. 252also.</p>

<p>JOhnim614 that was D, which i put</p>

<p>@Snayyan09</p>

<p>DO you happen to remember E? did i have a 13 in it? if so im screwed</p>

<p>Do you guys remember than standard deviation problem? It said something along the lines of what is the percentage of those who are at least 74.4 in tall? I put something like 4.6% I believe.</p>

<p>@Wudufuxpup </p>

<p>it was 2.3% i believe.</p>

<p>@johnkim614 no D had 13</p>