If x+a is a factor of 2x²+2ax+5x+10,find a.

If is a factor of the polynomial, it means that is a root of the polynomial.

In fact, if a polynomial has a root (i.e. ), then the polynomial is divisible by

In your case, you know that the polynomial is divisible by , so is a solution.

Let's evaluate and set it to zero:

We can check the if the polynomial becomes

And we're claiming that is a root of this polynomial:

4444444444444 i think