（a^2*b)^x*(a^x-1*b^2-y)^5=x^9*y^7
a^2x*b^x*a^5x-5*b^10-5y=x^9*y^7
a^(2x+5x-5)b^(x-10-5y)=x^9*y^7
所以2x+5y-5=9
x-10-5y=7
x=7
y=-2