a) (f+g)(x) = f(x) + g(x) = -4x + 5x = x
b) -9(x) = -9x? I have no idea what this means.
c) (f o g)(x) = (f(g(x)) = f(5x) = -4 (5x) = -20x
The length of line segment l n on which point m lines in between is 64 units. Option 4 is the correct option.
<h3>What is the length of line segment?</h3>
Length of a line segment is the distance of both the ends of it.
Point m lies between points l and n on line segment l n .
- The space between l and m is 10x 8.
- The space between m and n is 5x -4.
The value of line segment LN is,

The sum of LM and LN is equal to the line segment LN. Thus,

Put this value of x in the equation of line segment LN,

Thus, the length of line segment l n on which point m lines in between is 64 units. Option 4 is the correct option.
Learn more about the line segment here;
brainly.com/question/2437195