53 - 5 (4 + x) = 15
5 (4 + x) =53 - 15
5 (4+ x) = 110
(4 + x) =110:5
(4+ x) =22
x = 22 - 4
x= 18
\(5^3-5.\left(4+x\right)=15\)
\(125-5.\left(4+x\right)=15\)
\(5.\left(4+x\right)=125-15\)
\(5.\left(4+x\right)=110\)
\(\left(4+x\right)=110:5\)
\(\left(4+x\right)=22\)
\(x=22-4\)
\(x=18\)
T ủng hộ mk nhé bạn ^...^ ^_^
53 - 5(4 + x) = 15
=> 125 - 5(4 + x) = 15
=> 5(4 + x) = 110
=> 4 + x = 22
=> x = 18
125-5(4+x)=15
5(4+x)=125-15
5(4+x)=110
(4+x)=110:5
4+x=22
x=22-4
x=18
Vậy x=18
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