a) 128 - 3(x + 4) = 23
3(x + 4) = 128 -23
3(x + 4) = 105
x + 4 = 105 : 3
x + 4 = 35
x = 35 - 4
x = 31
\(a.128-3\left(x+4\right)=23.\)
\(3\left(x+4\right)=128-23\)
\(3\left(x+4\right)=105\)
\(x+4=105:3=35\)
\(x=35-4=31\)
\(b.\left[\left(4x+28\right)\cdot3+55\right]:5=35\)
\(\left(4x+28\right)\cdot3+55=35\cdot5=175\)
\(\left(4x+28\right)\cdot3=175-55=120\)
\(4x+28=120:3=40\)
\(4x=40-28=12\)
\(x=12:4=3\)
a, \(128-3.\left(x+4\right)=23\)
\(\Rightarrow\) \(3.\left(x+4\right)=105\)
\(\Rightarrow\) \(x+4=35\)
\(\Rightarrow\) \(x=31\)
b, \(\left[\left(4x+28\right).3+55\right]:5=35\)
\(\Rightarrow\) \(\left(4x+28\right).3+55=175\)
\(\Rightarrow\) \(\left(4x+28\right).3=120\)
\(\Rightarrow\) \(4x+28=40\)
\(\Rightarrow\) \(4x=12\)
\(\Rightarrow\) \(x=3\)
c) \(\left(12x-4^3\right)\cdot8^3=4\cdot8^4\)
\(12x-4^3=4\cdot8^4:8^4\)
\(12x-4^3=4\cdot8=32\)
\(12x=32+4^3=32+64=96\)
\(x=96:12=8\)
d) \(720:\left[41-\left(2x-5\right)\right]=2^3\cdot5\)
\(720:\left[41-\left(2x-5\right)\right]=40\)
\(41-\left(2x-5\right)=720:40=18\)
\(2x-5=41-18=23\)
\(2x=23+5=28\)
\(x=28:2=14\)
a) 128 - 3. (x+ 4) = 23
3. (x + 4) = 128 - 23
x + 4 = 105 : 3
x + 4 = 35
x = 35 - 4 = 31
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