(x+2)(x-3)-2(x-6)(x+5)-3(x平方-5x+17)
=(x²-x-6)-2(x²-x-30)-3(x²-5x+17)
=x²-x-6-2x²+2x+60-3x²+15x-51
=16x+3
=16*5.5+3
=91