How do you find the height of an isosceles triangle if its length is 12m and base 10m?

In a isosceles triangle, the altitude is also a median. If we draw the altitude, then two congruent right triangles are formed, with hypotenuse length of 12m and base length 5 m (10/2). So the length of hypotenuse, by the Pythagorean theorem is

h^2 = 12^2 - 5^2

h = √(144 - 25)

h = √119

h ≈ 10.9