Need help working College Level Math problems...?

I would just type out the questions, but diagrams are included in some of the questions. If this doesn't work:





http://professionals.collegeboard.com/pr鈥?/a>





Go here:





http://www.mvtechprep.org/links/links.ht鈥?/a>





Scroll down to Accuplacer and click on the College Board link. Click on "New Institution registration. Click on the collegeboard link. Click on smaple questions, then:





ACCUPLACER Sample Questions for Students (Revised December 2007) (.pdf/241k)


Requires Adobe Reader (latest version recommended).





CL Math is toward the bottom. I'm sorry for all the trouble.





The answer key is at the very bottom, but it doesn't help if you don't know how to work the problems. I hate to ask it, but I don't know how to work any of these, and I need somebody to show me. I tried and got different answers. Even if you only want to do 1 or 2, that will be appreciated so much. I've been studying for a week to take my placement test at my local community college, and I go to take it this afternoon. Just trying to get in all the studying I can. CLM is all I need help on. Thanks everybody|||Here's a bit of help





1.


2^(5/2)-2^(3/2) = [2^(3/2)](2-1) = 2^(3/2)





2.


1/x + 1/a = 1/b


1/x = 1/b - 1/a


1/x = (a - b)/ab


x = ab/(a-b)





3.


3x^2 - 2x + 7 = 0


x = [2 +- sqrt(2^2 - 4(3)(7))]/[2*3]


= 1/3 +- sqrt(-80)/6





So, (x-1/3)^2 = (+-sqrt(-80)/6)^2 = -80/36 = -20/9





4.


You want a line that has the same gradient. The gradient of y = 2x is 2. If you look at C, it is 2x-y = 4, which is the same as y = 2x-4, which also has gradient 2.





7.


Small square has side sqrt(5), and large has side sqrt(125).





Now, sqrt(125) = sqrt(5 * 25) = sqrt(5)sqrt(25) = 5sqrt(5).





So, total length needed is 4sqrt(5) + 4*5sqrt(5) = 24sqrt(5).








Hope that helps a bit.