SOLUTION: For the given rational function "f", find all values of "x" for which f(x) has the indicated value: f(x)=5x+21/x; f(x)= -38

Algebra ->  Rational-functions -> SOLUTION: For the given rational function "f", find all values of "x" for which f(x) has the indicated value: f(x)=5x+21/x; f(x)= -38      Log On


   

Question 429867: For the given rational function "f", find all values of "x" for which f(x) has the indicated value:
f(x)=5x+21/x; f(x)= -38
Answer by Gogonati(855) About Me  (Show Source):
You can put this solution on YOUR website!
Solution:Solve the equation:%285x%2B21%29%2Fx=-38, assuming that x, no zero.
x%285x%2B21%29%2Fx=-38x, multiplied both sides by x.
5x%2B21=-38x, write the equation in standard form
43x=-21, divide both sides by 43
x=-21%2F43
Answer:For x=-21/43 the value of f(x)=-38.
Check:
Done.