đm đang suy nghĩ câu đó

a=-1

\(\Leftrightarrow a=\dfrac{46}{5}\)

\(\Rightarrow b=-72-a=-72-\dfrac{46}{5}=-\dfrac{406}{5}\)

a)\(\Leftrightarrow\left|x+1,5\right|=4\)

\(\Leftrightarrow\left[{}\begin{matrix}x+1,5=4\\x+1,5=-4\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=2,5\\x=-5,5\end{matrix}\right.\)

c)\(\Leftrightarrow-14+21x=5+10x\)

\(\Leftrightarrow11x=19\Leftrightarrow x=\dfrac{19}{11}\)

D nha

\(=x^2\left(8x-3\right)-\left(8x-3\right)=\left(8x-3\right)\left(x^2-1\right)\)

B nha

C nha bạn