Bài 1:
a) $342:(x-2)=37$
$x-2=\dfrac{342}{37}$
$⇒x=\dfrac{342}{37}+2=\dfrac{416}{37}$
b) $(2x-45):3=215$
$2x-45=645$
$2x=645+45=690$
$⇒x=690:2=345$
c) $(3x-6).(4x-16)=0$
\(⇒\left[ \begin{array}{l}3x-6=0\\4x-16=0\end{array} \right.\)
\(⇒\left[ \begin{array}{l}3x=6\\4x=16\end{array} \right.\)
\(⇒\left[ \begin{array}{l}x=2\\x=4\end{array} \right.\)
Bài 2:
$a+4b=41⇒a=41-4b$
$⇒ab=(41-4b).b=0$
\(⇒\left[ \begin{array}{l}41-4b=0\\b=0\end{array} \right.\)
\(⇒\left[ \begin{array}{l}4b=41\\b=0\end{array} \right.\)
\(⇒\left[ \begin{array}{l}b=\dfrac{41}{4}\\b=0\end{array} \right.\)
\(⇒\left[ \begin{array}{l}a=0\\a=41\end{array} \right.\)
Vậy `(a,b)=(0, 41/4), (41,0)`
