If H is a subgroup of a group G, we define:

G/H = {xH : x belongs to G}

H\G = {Hx : x belongs to G}

Let G = D10 = {x, y| x^5 = y^2 = 1, yx =x^4(y)}

and K = {1, x, x^2,x^3,x^4} and H ={1,y}

How do you find G/K? and find the normal subgroup of D10

Can you give me some hints how to do this question plz?

Cheers