题目内容
求未知数x.
(1)3.4x+2.8=7.9;
(2)x-
x=
.
(1)3.4x+2.8=7.9;
(2)x-
3 |
5 |
5 |
8 |
分析:(1)3.4x+2.8=7.9,依据等式的性质,方程两边同时减2.8,再同时除以3.4求解.
(2)先计算x-
x=
x,然后等式的两边同时乘以
即可.
(2)先计算x-
3 |
5 |
2 |
5 |
5 |
2 |
解答:解:(1)3.4x+2.8=7.9
3.4x+2.8-2.8=7.9-2.8
3.4x=5.1
3.4x÷3.4=5.1÷3.4
x=1.5
(2)x-
x=
x=
x×
=
×
x=
3.4x+2.8-2.8=7.9-2.8
3.4x=5.1
3.4x÷3.4=5.1÷3.4
x=1.5
(2)x-
3 |
5 |
5 |
8 |
2 |
5 |
5 |
8 |
2 |
5 |
5 |
2 |
5 |
8 |
5 |
2 |
x=
25 |
16 |
点评:本题主要考查解方程,根据等式的性质进行解答即可.
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