\(\frac{12-3x}{32}=\frac{6}{4-x}\)
\(\Leftrightarrow\left(12-3x\right)\left(4-x\right)=6.32\)
\(\Leftrightarrow48-12x-12x+3x^2=192\)
\(\Leftrightarrow3x^2-24x-144=0\)
\(\left(a=3;b=-24;c=-144\right)\)
\(\Delta=b^2-4ac=\left(-24\right)^2-4.3.\left(-144\right)=2304>0\)
\(\sqrt{\Delta}=\sqrt{2304}=48\)
\(x_1=\frac{-b+\sqrt{\Delta}}{2a}=\frac{24+48}{2.3}=12\)
\(x_2=\frac{-b-\sqrt{\Delta}}{2a}=\frac{24-48}{2.3}=-4\)\
Vậy x1 = 12 ; x2 = -4
Học tốt !!! :)
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