Question

giá trị của x thỏa mãn 

x(x-1) -(x+1)^2=4

Answer 1

Ta có : \(x\left(x-1\right)-\left(x+1\right)^2=4.\)

\(\Leftrightarrow x^2-x-x^2-2x-1=4\)

\(\Leftrightarrow-3x=4+1\)

\(\Leftrightarrow-3x=5\)

\(\Leftrightarrow x=-\frac{5}{3}\)

Vậy \(x=-\frac{5}{3}\)

Answer 2

x(x-1)-(x+1)²=4

x²-x-(x²+1)=4

x²-x-x²-1=4

x²-x²-x-1=4

-x-1=4

-x=4+1

-x=5

\(\Rightarrow x=5\)