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In two or more complete sentences, explain how to use ordered pairs of points in f(x) = 2x + 5 and g(x)= x-5/2 to determine if f(x) and g(x) are inverses of each other. PLEASE EXPLAIN WITH WORDS IN TWO SENTENCES I NEED HELP ASAP

User Arkonautom
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Answer:

See below.

Explanation:

The given functions f(x) and g(x) are linear functions. Therefore, their inverses are a reflection about the line y = x.

The mapping rule for reflecting a point about the line y = x is:

  • (x, y) → (y, x)

To determine if f(x) and g(x) are inverses of each other:

  • Input the x-value of the ordered pair into one function.
  • Input the y-value of the ordered pair as the x-value of the other function.

If the y-value of one function equals the x-value of the other function (and the x-value of one function equals the y-value of the other function), the functions are inverses of each other.

Given functions:


\begin{cases}f(x) = 2x+5\\\\g(x)=(x-5)/(2) \end{cases}

Ordered pair: (2, 9)

Substitute x = 2 into f(x):


\implies f(2)=2(2)+5=9

Substitute x = 9 into g(x):


\implies g(9)=(9-5)/(2)=2

Therefore, the functions are inverses of each other since the x-value of function f equals the y-value of function g, and the y-value of function f equals the x-value of function g.

User M H
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