回答:
#y = -23x ^ 2 + 26x-12#
説明:
#y =(x + 4)(2x-2) - (5x-2)^ 2#
#y = x(2x-2)+ 4(2x-2) - (5x-2)(5x-2)#
#y = 2x ^ 2-2x + 8x-8 - 5x(5x-2)-2(5x-2)#
#y = 2x ^ 2-2x + 8x-8 - 25x ^ 2-20x + 4#
#y = 2x ^ 2-2x + 8x-8-25x ^ 2 + 20x-4#
#y = -23x ^ 2 + 26x-12#
お役に立てれば!