Question

giải phương trình

â) -3x² + 7x -4 = 0

Answer 1

\(-3x^2+7x-4=0\)

<=>\(-3x^2+3x+4x-4=0\)

<=>\(-3x\left(x-1\right)+4\left(x-1\right)=0\)

<=>\(\left(x-1\right)\left(4-3x\right)=0\)

<=>\(\left[{}\begin{matrix}x-1=0\\4-3x=0\end{matrix}\right.\)<=>\(\left[{}\begin{matrix}x=1\\x=\dfrac{4}{3}\end{matrix}\right.\)

Answer 2

-3x² + 4x + 3x - 4 =0

=> - x(3x-4) ...