Question

Mọi người giải giúp mình CÂU D với! Cảm ơn mọi người

Answer 1

a: \(5x+\dfrac{2}{3}=\dfrac{7}{9}\)

=>\(5x=\dfrac{7}{9}-\dfrac{2}{3}=\dfrac{7}{9}-\dfrac{6}{9}=\dfrac{1}{9}\)

=>\(x=\dfrac{1}{9}:5=\dfrac{1}{45}\)

b: \(\left|5-x\right|+\dfrac{1}{2}=8,5\)

=>\(\left|5-x\right|=8,5-0,5=8\)

=>|x-5|=8

=>\(\left[{}\begin{matrix}x-5=8\\x-5=-8\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=8+5=13\\x=-8+5=-3\end{matrix}\right.\)

c: \(16-\left(x+1,5\right)^2=\sqrt{49}\)

=>\(16-\left(x+1,5\right)^2=7\)

=>\(\left(x+1,5\right)^2=16-7=9\)

=>\(\left[{}\begin{matrix}x+1,5=3\\x+1,5=-3\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=3-1,5=1,5\\x=-3-1,5=-4,5\end{matrix}\right.\)

d: \(x^2\left(2^x-6\right)-2x^2=0\)

=>\(x^2\left(2^x-6-2\right)=0\)

=>\(x^2\left(2^x-8\right)=0\)

=>\(\left[{}\begin{matrix}x^2=0\\2^x-8=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=3\end{matrix}\right.\)