SOLUTION: Two resistors have a series resistance of 418 ohms and a parallel resistance of 104 ohms. Determine the two resistors (ohms). Put your answers in increasing order.

Algebra ->  Equations -> SOLUTION: Two resistors have a series resistance of 418 ohms and a parallel resistance of 104 ohms. Determine the two resistors (ohms). Put your answers in increasing order.       Log On


   

Question 726550: Two resistors have a series resistance of 418 ohms and a parallel
resistance of 104 ohms. Determine the two resistors (ohms).
Put your answers in increasing order.
R(series)=R1+R2
R(parallel)= (1/r1+1/r2)^-1

*this is all the info given* I believe its a 2 equations 2 unknown situation but not sure how to solve
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
r1+r2=418
1/r1 +1/r2=1/104
(r1+r2)/r1r2=1/104
104*(r1+r2)=r1r2
104*418=r1r2
r1r2=43472
r1= 43472/r2
r1+43472/r1= 418
r1^2+43472=418r1
r1^2-418r1+43472=0
Find the roots of the equation by quadratic formula

a= 1 , b= -418 , c= 43472

b^2-4ac= 174724 + -173888
b^2-4ac= 836
%09sqrt%28%09836%09%29=%0928.91%09
x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=( 418 + 28.91 )/ 2
x1= 223.46
x2=%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x2=( 418 -28.91 ) / 2
x2= 194.54
194.54 & 223.46 ohms