(20-2x)+|1/2y-1|=0 得：20-2x=0,1/2y-1=0 x=10 ,y=1/2 [3(x-7)]^17÷(y+1)^5 =9^17÷(3/2)^5 =3^34÷3^5×2^5 =3^29×2^5 =68 630 377 364 883 ×32 =1715759434100