SOLUTION: if f(x) = 10x-A/x-10 and f(4)=0, what is the value of A? Where is f not defined? A=? f is not defined when x=?

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Question 984382: if f(x) = 10x-A/x-10 and f(4)=0, what is the value of A?
Where is f not defined?
A=?
f is not defined when x=?
Found 2 solutions by solver91311, Timnewman:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


a. In order for the value of a rational function to be zero, the numerator must be equal to zero. Set the numerator equal to zero, substitute 4 in place of and then solve for .

b. A rational function is undefined when the denominator is zero. Set the denominator equal to zero and solve for

John

My calculator said it, I believe it, that settles it

Answer by Timnewman(323) About Me  (Show Source):
You can put this solution on YOUR website!
Hi dear,
If f(x)=%2810x-A%29%2F%28x-10%29
suppose f(4)=0
then,Put x=4 in the function,
%2840-A%29%2F%284-10%29=0
%2840-A%29%2F%28-6%29=0
40-A=0
A=40
the value of A is 40
f(x) is not defined at x=10