When factoring 6x2−7x−20 by grouping, how should the middle term be rewritten? It should be written as 8x−15x.

It should be written as −2x−5x.

It should be written as x−8x.

It should be written as −x−7x.
I think its B but im not sure

Is the given equation a quadratic equation? Explain.
x(x−6)=−5

The equation is not a quadratic equation because there is no x2-term.

The equation is a quadratic equation because there is an x2-term.

The equation is not a quadratic equation because the expression is not equal to zero.

The equation is not a quadratic equation because there is a term with degree higher than 2.

Which of the following is an example of the difference of two squares? x2−9

x3−9

(x+9)2

(x−9)2