Final answer:
The sum of the polynomials 9x and 4 is 9x + 4, which is the addition of a linear term and a constant term. This sum is not a quadratic equation and thus not solvable by the quadratic formula.
Step-by-step explanation:
To find the sum of the polynomials 9x and 4, you would simply add the two expressions together. Since one is a linear term and the other is a constant, they do not combine into a single term. Therefore, the sum of the polynomials is 9x + 4.
The rule mentioned, xPx9 = x(p+q), seems to pertain to the properties of exponents, where it represents multiplying powers with the same base. Specifically, if we have an exponent x raised to the power of p and multiply it by x raised to the power of q, the result is x raised to the power of (p+q).
Regarding solutions of quadratic equations, a standard quadratic equation is of the form ax2 + bx + c = 0, which can be solved using the quadratic formula or by completing the square. A polynomial like 9x + 4 is not a quadratic, as it lacks the x2 term, and thus cannot be solved using the quadratic formula.