Find the discriminant of the quadratic 5x^2 - 2x + 8 - 2x^2 + 6x + 2 - 2x^2 + 4x - 1.

Hi6942O Jun 20, 2024

#2**+1 **

Tottenham10, you did a great job with simplifying the quadratic, but there was one tiny mistake.

The descriminant is \(b^2-4ac\), not \(\sqrt{b^2-4ac}\). Other than that, you're good!

So, now we...

First, let's combine all like terms. We get;

\(x^{2}+8x+9\)

Now, the decriminant is \(b^2-4ac\) for any quadratics in the form of \(ax^2+bx+c\)

Thus, plugging in the numbers in the quadratic we have, we get

\(8^2-4(1)(9) \\ = 64- 36\\ =28\)

So 28 is our answer.

Thanks! :)

NotThatSmart Jun 20, 2024

#1**-1 **

If we combine all the like terms, the expression turns into \(x^2+8x+9\). The discriminant is \(\sqrt{b^2-4ac}\), so if we just plug in the values, we get \(\sqrt{64-36}=\sqrt{28}=2\sqrt{7}\).

Feel free to tell me if I made a mistake! :D

Tottenham10 Jun 20, 2024

#2**+1 **

Best Answer

Tottenham10, you did a great job with simplifying the quadratic, but there was one tiny mistake.

The descriminant is \(b^2-4ac\), not \(\sqrt{b^2-4ac}\). Other than that, you're good!

So, now we...

First, let's combine all like terms. We get;

\(x^{2}+8x+9\)

Now, the decriminant is \(b^2-4ac\) for any quadratics in the form of \(ax^2+bx+c\)

Thus, plugging in the numbers in the quadratic we have, we get

\(8^2-4(1)(9) \\ = 64- 36\\ =28\)

So 28 is our answer.

Thanks! :)

NotThatSmart Jun 20, 2024