a)$\frac{2}{3}$.x+$\frac{1}{5}$=$\frac{7}{10}$-x
b)3$\frac{1}{5}$x+16$\frac{3}{4}$=-13,25
c)(3$\frac{4}{5}$-2.x).1$\frac{1}{3}$=5$\frac{5}{7}$
a)$\frac{2}{3}$.x+$\frac{1}{5}$=$\frac{7}{10}$-x
b)3$\frac{1}{5}$x+16$\frac{3}{4}$=-13,25
c)(3$\frac{4}{5}$-2.x).1$\frac{1}{3}$=5$\frac{5}{7}$
`a)“2/3.x+1/5=7/10-x`
` 2/3.x + x= 7/10 – 1/5`
` 2/3.x + x= 7/10 – 2/10`
` 5/3.x = 5/10 = 1/2`
` x = 1/2 : 5/3`
` x = 1/2 . 3/5`
` x = 3/10`
`b)“3` `1/5x+16“3/4=-13,25`
`16/5x + 67/4 = (-1325)/100`
`16/5x = (-1325)/100 – 67/4`
`16/5x = 5300/400 – 6700/400`
`16/5x = (-1400)/400 = (-7)/2`
` x = (-7)/2 : 16/5`
` x = (-7)/2 . 5/16`
` x = (-35)/32`
Câu `c )` làm sau
a
)
a
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2
3
.
x
+
1
5
=
7
10
−
x
2
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2
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x
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1
2
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1
2
:
5
3
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1
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1
2
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3
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1
2
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b
)
b
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3
3
1
5
x
+
16
1
5
x
+
16
3
4
=
−
13
,
25
3
4
=
–
13
,
25
16
5
x
+
67
4
=
−
1325
100
16
5
x
+
67
4
=
–
1325
100
16
5
x
=
−
1325
100
−
67
4
16
5
x
=
–
1325
100
–
67
4
16
5
x
=
5300
400
−
6700
400
16
5
x
=
5300
400
–
6700
400
16
5
x
=
−
1400
400
=
−
7
2
16
5
x
=
–
1400
400
=
–
7
2
x
=
−
7
2
:
16
5
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–
7
2
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16
5
x
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−
7
2
.
5
16
x
=
–
7
2
.
5
16
x
=
−
35
32
x
=
–
35
32
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