问题
解答题
(1)2×(-5)+23-3÷12; (2)1
(3)x-
(4)
|
答案
(1)原式=-10+8-4
=-6;
(2)原式=
×[3×3 2
-1]-4 9
×(-8)1 3
=
×[3 2
-1]+4 3 8 3
=
×3 2
+1 3 8 3
=
+1 2 8 3
=
;19 6
(3)x-
=2-x-1 2 x+2 3
6x-3(x-1)=12-2(x+2)
6x-3x+3=12-2x-4
6x-3x+2x=12-4-3
5x=5
x=1;
(4)
[x-1 2
(x-1)]=1 3
(2x+1)3 4
x-
(x-1)=3x+1 3 3 2
6x-2x+2=18x+9
6x-2x-18x=9-2
-14x=7
x=-
.1 2