SOLUTION: What Quadratic Equation has the following solutions: X= 4 +/- Square root 7?

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: What Quadratic Equation has the following solutions: X= 4 +/- Square root 7?      Log On


   

Question 19718: What Quadratic Equation has the following solutions: X= 4 +/- Square root 7?
Answer by xcentaur(357) About Me  (Show Source):
You can put this solution on YOUR website!
roots of the equation: 4 +- sqrt(7)
sum of the roots: (4+sqrt(7))+(4-sqrt(7)) = 4+4= 8
product of the roots: (4+sqrt(7))*(4-sqrt(7)) = (16-7)= 9


in a quadratic equation of form
ax%5E2%2Bbx%2Bc=0
(-b/a)=sum of the roots
(c/a)=product of the roots

let co-efficient of x^2 be 1
then we get,
(-b)=sum,(c)=product
-b=8,c=9
b=-8,c=9
substituting these values in our above equation,
ax%5E2%2Bbx%2Bc=0
x%5E2-8x%2B9=0


Hope this helps,
Prabhat