hey need help

1)3-2x/5-x-7/6

working out

6(3-2x)-5(x-7) ≤ -2(30)

-17x ≤ -113

x -113/-17 ?? wrong

answer is -7/17

2)a/x+a + b/x-b = a+b/x+c, for x

first i multiply everything on the denominator to get the same denominator therefore mulitpying the top

so, (ax-b)(x+c) + (bx+ba)(x+c) = (ax^2+a^2+bx+ba)(x-b)

expanded it and then collected like terms.

so, axc - bx+bxc+acb-a^2x+b^2 x = -a^2 b -b^2a-bac+bc

then where to ?

answer is ab/a-b-c

3)the formula for converting degrees Celsius,C, to degrees Farenheit,F, is F=9/5C+32

a)If xC=xF, find x.

b)If kF=(-3k)C, find k

thanks for anyone who can help