Question

A man 1.4m tall looks at a bird on a tower at an angle of elevation of 45`.If the man is 10m away from the tower,how tall is that tower

Answer 1

Make a sketch, extend the line from the top of the tower to the man until it hits the base line

You now have a small isosceles right-angled triange within a larger one.
so the smaller one has legs 1.4 m and 1.4 m.
So the base of the larger is 1.4+10 or 11.4 m, which means that the height must also be 11.4 m