I have done the work, but i need someone to verify if they are correct.

Simplify.

a)4x^2y^5/x^4y^2 = 4x^2y^3

b)3xy/9x^2-12x = 3y/3x-4

c) 4x^2-20x/x+3 * 4x^2-1/2x^2-9x-5 = 4x^2(2x-1)/(x+3)

d) 4x+1/3x-5 + 2x/12x-20 = (9x+2)/(6x-10)

e) how would i simplify 3x-1/x^2+4x+3 - x+6/2x^2+7x+1