SOLUTION: The quadratic x^2+7x+20 has the same roots as the quadratic Ax^2+Bx+1. What is A+B?

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: The quadratic x^2+7x+20 has the same roots as the quadratic Ax^2+Bx+1. What is A+B?      Log On


   



Question 1023632: The quadratic x^2+7x+20 has the same roots as the quadratic Ax^2+Bx+1. What is A+B?
Answer by ikleyn(52810) About Me  (Show Source):
You can put this solution on YOUR website!
.
The quadratic x^2+7x+20 has the same roots as the quadratic Ax^2+Bx+1. What is A+B?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

1.  Since the two quadratic equations have the same roots, their coefficients are proportional.

2.  It implies that A = 1%2F20 and B = 7%2F20.

    Then A + B = %281+%2B+7%29%2F20 = 8%2F20 = 2%2F5.