SOLUTION: What is the larger root of 1/5x^2=1/3x+2/15

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Question 331218: What is the larger root of 1/5x^2=1/3x+2/15
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Response to student comment. It is always OK to use the quadratic formula.
Indeed, there are many, which will not factor. and that is the only way to do it.
If you can see that it will factor, it saves time and energy to do it that way.
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What is the larger root of
%281%2F5%29x%5E2=%281%2F3%29x%2B%282%2F15%29
multiplying by 15 gets rid of the denominators
3x^2 = 5x + 2
:
3x^2 - 5x - 2 = 0
Factors
(3x + 1)(x - 2) = 0
x = 2 is the larger root
;
:
Check solution in the original equation
%281%2F5%292%5E2=%281%2F3%292%2B%282%2F15%29
%284%2F5%29=%282%2F3%29%2B%282%2F15%29
%2812%2F15%29=%2810%2F15%29%2B%282%2F15%29