Maths Help Needed :(

[Tohru Kyo Sohma]

Ok...so i will soon be starting my university and i have to appear for my placement test!
The test is for Business maths and English
I have tried the maths questions from a sample test paper and am finding it difficult as i haven't practiced maths for a year!
Please help me out with my questions!
 
1. Evaluate (3x^4y^-8/5x^-2y^4z^2)^-2?
2. Find the domain of the function f(x)=2 ?-2+x

Please help me out!

[astarmathsandphysics]

Give me an hour

[astarmathsandphysics]

Try this. The second question is not clear. You can post again.

[Tohru Kyo Sohma]

Thanks astarmathsandphysics
I got how to do the first one
the second one where a question mark appears it is supposed to be a root i copied a symbol but it didn't appear!

[astarmathsandphysics]

If  root x then domain is x>=0

[Tohru Kyo Sohma]

One factor of 18x^2 -32 is
(a) 9x-32
(b) 9x-16
(c) 3x-2
(d) 3x+4
(e) none of the above
?
which one is it?

[Tohru Kyo Sohma]

If 2a-b/b=3 then b/a is equal to:
a. 2
b. -0.5
c. 0.5
d. -2
e. none of the above

I think its C
i got this by apply the algebric formula and got a=4 b=2
what do you guys think?

[astarmathsandphysics]

One mo

[astarmathsandphysics]

18x^2-32=2(9x^2-16)=2(3x-4)(3x+4)

[astarmathsandphysics]

(2a-b)/b=2a/3-b/b=2a/b-1=3
2a/b=4 so a/b=2 so b/a=1/2=0.5

[Tohru Kyo Sohma]

18x^2-32=2(9x^2-16)=2(3x-4)(3x+4)

so it's D?

[Tohru Kyo Sohma]

(2a-b)/b=2a/3-b/b=2a/b-1=3
2a/b=4 so a/b=2 so b/a=1/2=0.5

so c is right?

[Tohru Kyo Sohma]

Solve 2x^2+6x-3=0
options:
a. x=(-3+- root of 15)/2
b. x=(-3+- root of 3)/2
c. x=(3+- root of 15)/2
d. x=-3+-root of 15
e. none of the above

I think its E?
Is it right?

[astarmathsandphysics]

D then C for the first 2.

[astarmathsandphysics]

D then C for the first 2.
For the third I make it A using the quadratic formula.