Algebra Help!

So I was recently accepted into a business program at a local university with the pretenses of finishing up Business Calc over the summer. Problem is, I need to test in to this math class through a placement exam at another local junior college and I haven't taken math in a number of years so I'm a tad bit rusty. Not wanting to go in to this test blind and unprepared I downloaded their practice exam and began reviewing on my own.
If anyone could possibly take their time and go over this practice exam and write out how they obtained the answers I would be more than appreciative!
The answers are on the bottom of the page for checking purposes.
Thank you ahead of time.


This is the link to the GWC homepage where the test is posted.

 

bump! so I remember the majority of this, but having trouble with numbers 3 & 5 if anyone could chime in here with work shown?
Again, thanks ahead of time.

 

3

When multiplying like-bases, add the exponents. When dividing like-bases, subtract the exponents. The exponents will be: 6a+2-2a so you get the final exponent of 4a+2.
X^4a+2

 

5

Write the equations one above the other so that like terms line up. Add the two equations together. You get 3x=9. Divide both side by 3 to get the x by itself. You get x=3. Put 3 back into either equation in place of the x, say the first one: 2(3)+y=8. 6+y=8. Subtract 6 from both sides. Y=2.

 

5. Take the second equation x-y=1 and add y to both sides, yielding x=y+1 Then plug that value of x into the original equation. 2*(y+1) + y = 8 or, 2y + 2 + y = 8, which yields 3y = 6, or y = 2. I apologize for the run-on of the wording. I haven't figured out why my posts do not reflect the spacing and paragraphs of what I submit.