问题
解答题
(1)计算:-42×
(2)
|
答案
(1)原式=-42×
+|-2|3×(-1 (-4)2
)31 2
=-16×
+8×(-1 16
),1 8
=-1+(-1)
=-2.
(2)
-2x+1 3
=15x-1 6
去分母得:2(2x+1)-(5x-1)=6,
去括号得:4x+2-5x+1=6,
移项得:4x-5x=6-2-1,
合并同类项得:-x=3,
两边都乘以-1得:x=-3.