Question

Giải phương trình

3x−x(x−2)=−(x+1)^2

Answer 1

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

\(\Leftrightarrow3x-x^2+2x=-\left(x^2+2x+1\right)\)

\(\Leftrightarrow5x-x^2=-x^2-2x-1\)

\(\Leftrightarrow-x^2+x^2+5x+2x=-1\)

\(\Leftrightarrow7x=-1\)

\(\Leftrightarrow x=\left(-1\right)\div7\)

\(\Leftrightarrow x=-\dfrac{1}{7}\)

Ko bt đúng or sai :>

Answer 2

3x -x(x-2)= -(x+1)^2

<=>3x -x^2 +2x= -x^2-2x -1

<=> -x^2 +x^2 +5x +2x=-1

<=>7x= -1

<=>x= -1/7