题目内容
解方程:
+
+
+
+
=5.
| x-20 |
| 3 |
| x-18 |
| 5 |
| x-16 |
| 7 |
| x-14 |
| 9 |
| x-12 |
| 11 |
考点:解一元一次方程
专题:
分析:把式子拆分
+
+
+
+
=
+
+
+
+
+5,观察上式子由于右边式子分子加分母都等于23,而5=
+
+
+
+
,因此右式=23×(
+
+
+
+
),所以x=23
| x |
| 3 |
| x |
| 5 |
| x |
| 7 |
| x |
| 9 |
| x |
| 11 |
| 20 |
| 3 |
| 18 |
| 5 |
| 16 |
| 7 |
| 14 |
| 9 |
| 12 |
| 11 |
| 3 |
| 3 |
| 5 |
| 5 |
| 7 |
| 7 |
| 9 |
| 9 |
| 11 |
| 11 |
| 1 |
| 3 |
| 1 |
| 5 |
| 1 |
| 7 |
| 1 |
| 9 |
| 1 |
| 11 |
解答:解:
+
+
+
+
=5.
+
+
+
+
=
+
+
+
+
+5,
x(
+
+
+
+
)=23×(
+
+
+
+
),
x=23.
| x-20 |
| 3 |
| x-18 |
| 5 |
| x-16 |
| 7 |
| x-14 |
| 9 |
| x-12 |
| 11 |
| x |
| 3 |
| x |
| 5 |
| x |
| 7 |
| x |
| 9 |
| x |
| 11 |
| 20 |
| 3 |
| 18 |
| 5 |
| 16 |
| 7 |
| 14 |
| 9 |
| 12 |
| 11 |
x(
| 1 |
| 3 |
| 1 |
| 5 |
| 1 |
| 7 |
| 1 |
| 9 |
| 1 |
| 11 |
| 1 |
| 3 |
| 1 |
| 5 |
| 1 |
| 7 |
| 1 |
| 9 |
| 1 |
| 11 |
x=23.
点评:此题考查了一元一次方程的解法,这题应该是考察答题者的观察能力,解题的关键是:把式子拆分
+
+
+
+
=
+
+
+
+
+5.
| x |
| 3 |
| x |
| 5 |
| x |
| 7 |
| x |
| 9 |
| x |
| 11 |
| 20 |
| 3 |
| 18 |
| 5 |
| 16 |
| 7 |
| 14 |
| 9 |
| 12 |
| 11 |
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