SOLUTION: if the roots of one less than twice a number to the square of the number is 5/9. find the number. please help me how to solve this.

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: if the roots of one less than twice a number to the square of the number is 5/9. find the number. please help me how to solve this.      Log On


   

Question 788323: if the roots of one less than twice a number to the square of the number is 5/9. find the number. please help me how to solve this.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Assume you mean:
if the rato of one less than twice a number to the square of the number is 5/9:
:
%28%282x-1%29%29%2Fx%5E2 = 5%2F9
cross multiply
9(2x-1) = 5x^2
18x - 9 = 5x^2
arrange as a quadratic equation on the right
0 = 5x^2 - 18x + 9
This factors to
(5x-3)(x-3) = 0
The integer solution is all we want here
x = 3
:
;
See if that works
%28%282%283%29-1%29%29%2F3%5E2 = 5%2F9