9/21 because it can still be reduced to 3/7
F(3) = 16, you simply plug in 3 for x to find the answer.
Its C. 113 ft because the height and the perimider of the trinagle
How to solve:

-

Write all numerators above the least common denominator which is 24 in this case.

Subtract the numbers

Alternate form: 0.458333
The final, simplified, fraction answer is:
Answer:
y=-1/2x+2
the y-intercept is at 2 and the slope is -1/2
meaning the y coordinates with move down 1 while the x coordinates will move 2 in a positive (right) direction