» CC HOME » FORUM HOME

 College Confidential Sat/act math questions help!!!
 User Name Remember Me? Password New User

Welcome to College Confidential!
The leading college-bound community on the web
Join for FREE now, and start talking with other members, weighing in on community polls, and more.

Also, by registering and logging in you'll see fewer ads and pesky welcome messages (like this one)!
 Discussion Menu »Discussion Home »Help & Rules »Latest Posts »NEW! CampusVibe™ »Stats Profiles Top Forums »College Chances »College Search »College Admissions »Financial Aid »SAT/ACT »Parents »Colleges »Ivy League Main CC Site »College Confidential »College Search »College Admissions »Paying for College Sponsors SuperMatch - The Future of College Search! CampusVibe - Almost As Good As A Campus Visit!
 10-18-2012, 07:23 PM #1 Member   Join Date: Jan 2011 Posts: 318 Sat/act math questions help!!! The graph of y= -5x^2+9 passes through (1,2a) in the standard (x,y) coordinate plane. What is the value of a? Discount tickets to a basketball tourney sell for \$4.00 each. Enrico spent \$60.00 on discount tickets, \$37.50 less than if he had bought the tickets at the regular price. what was the regular ticket price? For what value of a would the following system of equations have an infinite number of solutions? 2x-y=8 6x-3y=4(a) Reply
 10-18-2012, 07:33 PM #2 Member   Join Date: Jan 2011 Posts: 318 bump. bump! come on you guys, these should be simple for most of yall! Reply
 10-18-2012, 07:52 PM #3 Junior Member   Join Date: Mar 2012 Posts: 48 Ok, so I think you would just plug in the coordinates in the equations and solve for a, Enrich bought 15 tickets, so \$60+\$37.50= x = 97.5/15= \$6.50 The third one I'm not sure, but just solve for one variable at a time Reply
 10-18-2012, 08:44 PM #4 Member   Join Date: Jan 2011 Posts: 318 bump for the last one you guys!!!! Reply
 10-18-2012, 10:18 PM #5 Junior Member   Join Date: Oct 2012 Posts: 118 Multiply the top equation by three so the two match. 6x-3y=24 6x-3y=4a For the system to have infinite solutions, the two must be equivalent to each other. Since we made the variable equal already, we just have to find a number a such that 24=4a. The answer is 6. Reply
 10-19-2012, 02:44 AM #6 Senior Member   Join Date: Mar 2012 Location: Cambridge, MA Posts: 1,913 ^ I agree, the answer to the third one is a = 6. This is because both equations will then be equivalent, in which the solution set is a line (infinitely many points). Reply
 10-20-2012, 01:09 PM #7 Member   Join Date: Jan 2011 Posts: 318 Thanks you guys, your the best! Reply
 10-24-2012, 05:07 PM #8 Junior Member   Join Date: May 2012 Posts: 55 Hey, are those questions from the McGraw Hill's prep book? Im using McGraw Hill's and the questions are the same exact type of questions that are in my book lol Reply

 Bookmarks