Question

Các bạn giúp mik đi! Mik đg cần gấp

Answer 1

\(6x-9-x^2=-\left(x-3\right)^2\)

Answer 2

\(6x-9-x^2=-\left(x^2-6x+9\right)=-\left(x-3\right)^2\)

Answer 3

\(6x-9-x^2=-\left[-\left(6x-9-x^2\right)\right]=-\left(x^2-6x+9\right)=-\left(x-3\right)^2\)