(2x-5)(3x+2)-6(x+1)(x-2)
=6x²+4x-15x-10-6(x²+x-2x-2)
=6x²-11x-10-6(x²-x-2)
=6x²-11x-10-6x²+6x+12
= -5x+2
x=0.2
原式= -5x0.2+2= -1+2=1