Answer:
The inverse will be:

Step-by-step explanation:
In order to find the inverse of the equation, we do a variable change, since we are finding the inverse, :



Now solve for y'.
First add 4 in both sides of the equation and change to the left y'.

= x + 4
Second divide by 9
/9 = (x + 4)/9
= (x + 4)/9
Now you will have to clear y, with the square root.
[/tex] =
Simplifying terms


You can check the answer by doing the evaluation of the following equation:
(f o
) (x)
substitute the equation for y' or inverse function 
f(
)
Now substitue the value into f(x)
You will have

=x
Its an acute triangle by angles.
Its a NONE by sides.
39 x 5 = (30 x 5) + (9 x 5) = 150 + 45 = 195
He did not change the sign of operation when 28 crossed the equals sign.