已知x方-5x=14,求(x-1)(2x-1)-(x+1)方+1的值

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已知x方-5x=14,求(x-1)(2x-1)-(x+1)方+1的值

已知x方-5x=14,求(x-1)(2x-1)-(x+1)方+1的值
已知x方-5x=14,求(x-1)(2x-1)-(x+1)方+1的值

已知x方-5x=14,求(x-1)(2x-1)-(x+1)方+1的值
x方-5x=14
x方-5x-14 = 0
(x+2)(x-7) = 0
x = -2,或x = 7
x = -2时:
(x-1)(2x-1)-(x+1)方+1 = -3*(-5)-(-1)方+1 = 15-1+1 = 15
x = 7时:
(x-1)(2x-1)-(x+1)方+1 = 6*13-(-7)方+1 = 78-49+1 = 30