Answer:
One of the altitude formed from the vertex to the base and its magnitude given as 12cm
There is also a hypotenuse whose length is 15cm
By pythagorean theorem b^2 +a^2= c^2
so 12^2+a^2 = 15^2
=> 144+a^2 = 225
=> a^2 = 225-144
=> a^2 = 81
so the length of a = √81 = 9 cm (ans)
Hope it helps
