Question

Need help anything helps thanks

Answer 1

A binomial squared is written like

$x^2+2ax+a^2$

So, we have $2a=6 \iff a=3$

So, we want to complete the square $(x+3)^2 = x^2+6x+9$

We can add and subtract 9 to write

$x^2+6x = x^2+6x+(9-9) = (x^2+6x+9)-9 = (x+3)^2-9$