Question

PLS HELP

If F(x)=
`(C-x)/(D-x)`, F(-2) is undefined, and F(-1)=4, What is the value of C?

Answer 1

C = -5

Explanation:

Functions

F(x) is defined as:

`\displaystyleF(x)=(C-x)/(D-x)`

We know F(-2) is undefined. It comes from the fact that the denominator is 0 for this value of x, thus:

D - (-2) = 0

Solving:

D = -2

Substituting:

`\displaystyleF(x)=(C-x)/(-2-x)`

We also know F(-1) = 4:

`\displaystyle (C-(-1))/(-2-(-1))=4`

`\displaystyle (C+1)/(-2+1)=4`

`\displaystyle (C+1)/(-1)=4`

Multiplying by -1

C + 1 = -4

Solving for C:

C = -5