Lời giải:
$200-18:(42:3\times x-13)-28=154$
$200-28-18:(42:3\times x-13)=154$
$172-18:(42:3\times x-13)=154$
$18:(42:3\times x-13)=172-154=18$
$42:3\times x-13=18:18=1$
$14\times x-13=1$
$14\times x=13+1=14$
$x=14:14=1$
\(200-18:\left(42:3\times x-13\right)-28=154\)
\(200-18:\left(42:3\times x-13\right)=182\)
\(18:\left(42:3\times x-13\right)=200-182\)
\(18:\left(42:3\times x-13\right)=18\)
\(42:3\times x-13=18:18\)
\(42:3\times x-13=1\)
\(42:3\times x=1+13\)
\(42:3\times x=14\)
\(14\times x=14\)
\(x=14:14\)
\(x=1\)
Ta có: \(200-18:\left(42:3x-13\right)-28=154\)
\(\Leftrightarrow172-18:\left(42:3x-13\right)=154\)
\(\Leftrightarrow18:\left(42:3x-13\right)=18\)
\(\Leftrightarrow42:3x-13=1\)
\(\Leftrightarrow42:3x=14\)
\(\Leftrightarrow3x=3\)
hay x=1
