Y(y+4)-y squared =6 is a quadratic equation

I hope your question is to find whether y(y+4)-y squared =6 is a quadratic equation or not.

Let's simplify the left side of the equation. So,

y (y + 4) - y²

= y² + 4y - y²

= 4y Since y² and -y² has cancel out.

So, the above equation changes to

4y = 6.

Notice here the square term has vanish.

So, it's not a quadratic equation.

I hope it's helps you!