(1)-3a-(-2a+2b-c)
=-3a+2a-2b+c
=-a-2b+c
(2)4a²+3b²+2ab-4ab-4b²
=4a²-2ab-b²
(3)3x-4x²+7-3x+2x²+1
=-2x²+8
(-8x²+6x)-(5x²-4x+1)
=-13x²+10x-1
=-13×(-1)²-4×(-1)-1
=-13+4-1
=-10
(1)-3a-(-2a+2b-c)
=-3a+2a-2b+c
=-a-2b+c
(2)4a²+3b²+2ab-4ab-4b²
=4a²-2ab-b²
(3)3x-4x²+7-3x+2x²+1
=-2x²+8
(-8x²+6x)-(5x²-4x+1)
=-13x²+10x-1
=-13×(-1)²-4×(-1)-1
=-13+4-1
=-10