Question

Rezolvati ecuatia
X·(X-25)=4400

Answer 1

$x(x-25)=4400 \\ x^2-25x=4400 \\ x^2-25x-4400=0 \\ (x+55)(x-80)=0 \\ x+55=0 \\ x=0-55 \\ x=-55 \\ x-80=0 \\ x=0+80 \\ x=80 \\ S=\{-55;80\}$