Question 827726
The triangle is 10m on each side.
set x = height
Using Pythagorean theorem
 x^2 + (5 which is is 1/2 of the base)^2 = 10^2
 x^2 + 5^2  = 10^2
 x^2 + 25 = 100
subtract 25 from each side
 x^2 = 75
 x = sqrt(75) = 8.66m