The sum of the roots of a quadratic equation is 7, the product of the roots is 9. What is the
equation?
Answer:
27) C
To solve this, we need to use the equation:
(x – a) (x – b) = (x² – xb – xa + ab), where a and b are the solutions.
x² – xb – xa + ab = x² – x (b + a) + ab
We know that the sum of the roots of the quadratic equation is 7 and the product is 9.
i.e. (a + b) = 7 and (ab) = 9.
So, we need to substitute these values in. We get the equation:
x² – x (b + a) + ab = (x² – 7x + 9)
Hence the answer is C.