Answer: 16 m
Step-by-step explanation:
Using the Pythagorean theorem you can find the height of the mast.
The formula is;
a² + b² = c²
a is one side of the triangle such as the width
b is another side such as the height
c is the hypotenuse which is the longest side.
c will therefore be 20m.
a will be 12m
12² + b² = 20²
b² = 400 - 144
b² = 256
b = √256
b = 16m