问题
解答题
解方程.
(1)3(x2-2x-6)-3x(x-5)=0;
(2)x(2x-4)+3x(x-1)-5x(x-3)+8.
答案
(1)方程即:3x2-6x-18-3x2+15=0,
即-6x-18+15=0,
移项,得:-6x=18-15,
即-6x=3,
则x=-
;1 2
(2)原式=2x2-4x+3x2-3x-5x2+15x+8
=8x+8.
解方程.
(1)3(x2-2x-6)-3x(x-5)=0;
(2)x(2x-4)+3x(x-1)-5x(x-3)+8.
(1)方程即:3x2-6x-18-3x2+15=0,
即-6x-18+15=0,
移项,得:-6x=18-15,
即-6x=3,
则x=-
;1 2
(2)原式=2x2-4x+3x2-3x-5x2+15x+8
=8x+8.