Answer:
10 ft to nearest foot.
Step-by-step explanation:
We use the Pythagoras theorem:
12^2 = 6^2 + h^2 where h is the height on the barn
h^2 = 12^2 - 6^2
h^2 = 144 - 36 = 102
h= √108 = 10.39
X=8 & z=66
because vertical angles are congruent
The directrix of the parabola is 
<h3>How to determine the equation of the directrix?</h3>
The parabola equation is given as:

A parabola is represented as:

By comparing both equations, we have:
4p = 1/4 ==> p = 1/16
-k= 3 ==> k = -3
The directrix is represented as:
y = k - p
So, we have:

Take the LCM

Evaluate

Hence, the directrix of the parabola is 
Read more about parabola at:
brainly.com/question/1480401
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