Answer: C
Step-by-step explanation:
Construct the segment connecting the point where the height meets to the base to where the slant height meets the base.
This forms a right triangle with legs of length 3.5 and 6.
So, by the Pythagorean theorem, [tex]x=\sqrt{3.5^2 + 6^2} \approx 6.9[/tex]
