| 3.5X+0.5X=12.8 | 45x÷3=90 | (7-1.4)x+5=7.8. |
4X=12.8,
4X÷4=12.8÷4,
X=3.2;
(2)45x÷3=90,
15x=90,
15x÷15=90÷15,
x=6.
(3)(7-1.4)x+5=7.8,
5.6x+5=7.8,
5.6x+5-5=7.8-5,
5.6x÷5.6=2.8÷5.6,
x=0.5.
编辑:chaxungu时间:2026-04-27 13:38:23分类:小学数学题库
| 3.5X+0.5X=12.8 | 45x÷3=90 | (7-1.4)x+5=7.8. |