Need help with basic algebra please

i need help with these problems thanks (:

1. (x + 2y) * 6x-y)
2. (5x - 9)^2
3. (x-4) (x^2 - 5x + 7)
4. ( 3x +1) - ( 4x -2)
5. 8x(x^2 + 4x - 9)
6. 3(7+c) = 2(9 + c) for number 6, i need to solve for C
7.4x - 5y - 14 for number 7, i need to solve for y

thanks guys i dont get it =/

1. 6x²-xy+ 12xy-2y² =
6x² + 11xy - 2y² (There was supposed to be parentheses next to the 6x, right?)

2. 25x² - 45x - 45x + 81 =
25x² -90x + 81

3. x³- 5x² + 7x - 4x² + 20x -28 =
x³ - 9x² + 27x - 28

4. 3x + 1 - 4x +2 =
-x +3

5. 8x³ + 32x² - 72x

6. 21 +3c = 18 +2c
c = -3

7. ummm.. did you leave out a sign or something? because otherwise, i don't think you can solve that...

if it was 4x -5y = 14

-5y = -4x + 14

y = 4/5 x - 14/5



for the other problems, whatever is after the equals sign is the answer!!

hope this helps ;)

6x^2+11xy-2y^2
25x^2-90x+81

x^2-5x+7
x-4
----------------
-4x^2+20x-28
x^3-5x^2+7x
---------------------------
x^3-9x^2+27x-28

-x+1
8x^3+32x^2-72x
21+3c=18+2c
--------------------
c=-3

4x-5y-14
-5y=-4x+14
===============
y= 4/5x-14/5