题目内容
解方程.
x-
+
=1 (
+3.2)x=
.
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分析:(1)先运用减法的性质改写成
x-(
-
)=1,即
x-
=1,再根据等式的性,两边同加上
,再同乘
即可;
(2)先计算
+3.2=4,原式变为4x=
,再根据等式的性,两边同乘
即可.
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(2)先计算
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解答:解:(1)
x-
+
=1,
x-(
-
)=1,
x-
=1,
x-
+
=1+
,
x=
,
x×
=
×
,
x=
;
(2)(
+3.2)x=
,
(0.8+3.2)x=
,
4x=
,
4x×
=
×
,
x=
.
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x=
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(2)(
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(0.8+3.2)x=
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4x=
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4x×
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x=
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点评:此题考查了根据等式的性质解方程,即等式两边同加、同减、同乘或同除以一个数(0除外),等式的左右两边仍相等;注意等号上下要对齐.
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