问题
解答题
解方程. x+0.75-
2x+
2.7X-1.6=38.9. |
答案
(1)x+0.75-
=0.15,3 5
x+0.15=0.15,
x+0.15-0.15=0.15-0.15,
x=0,
(2)2x+
=4.625,5 8
2x+
-5 8
=4.625-5 8
,5 8
2x=4,
x=2,
(3)
-2X=4 5
,1 4
-2x+2x-4 5
=1 4
+2x-1 4
,1 4
=2x,11 20
2x=
,11 20
x=
,11 40
(4)2.7x-1.6=38.9,
2.7x-1.6+1.6=38.9+1.6,
2.7x=40.5,
2.7x÷2.7=40.5÷2.7,
x=15.