a,45 + x = 2x e, 4x + 3x = 70
\(\Rightarrow2x-x=45\) \(\Rightarrow7x=70\)
\(\Rightarrow x=45\) \(\Rightarrow x=10\)
Vậy x = 45 Vậy x = 10
b, 2 + x - 4 = 12 f, 6x - 18 = 0
\(\Rightarrow2+x=12+4\) \(\Rightarrow6x=18\)
\(\Rightarrow2+x=16\) \(\Rightarrow x=3\)
\(\Rightarrow x=14\) Vậy x = 3
Vậy x = 14 g, 72x : 36 = 2
c, 10 + x = 5 + 2x \(\Rightarrow72x=72\)
\(\Rightarrow2x+x=10+5\) \(\Rightarrow x=1\)
\(\Rightarrow3x=15\) Vậy x = 1
\(\Rightarrow x=5\) h, 13 + x = 5 + 2x
Vậy x = 5 \(\Rightarrow2x+x=13+5\)
d, 42 - 2x = 12 \(\Rightarrow3x=18\)
\(\Rightarrow2x=42-12\) \(\Rightarrow x=6\)
\(\Rightarrow2x=30\) Vậy x = 6
\(\Rightarrow x=15\)
Vậy x = 15
45 + x = 2x
x =45
2 + x - 4 =12
x - 2 = 12
x = 14
10 +x = 5 + 2x
-x = -5
x = 5
42 - 2x = 12
-2x = -30
x = 15
4x + 3x = 70
7x = 70
x = 10
6x - 18 = 0
6x = 18
x = 3
72x : 36 = 2
72x = 72
x = 1
13 +x = 5 +2x
-x = -8
x = 8
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