posted by Rin on .
The eaves of a roof sloping at 23° overhand the walls, the edge of the roof being 75 cm from the top of the wall. The top of the wall is 5.4 metres above the ground. What is the height above the ground of the edge of the roof, to the nearest centimeter?
If I am picturing this correctly, a right triangle is formed, with the hypotenuse c = 75 cm.
Since the top of the wall is 5.4 m above ground, 5.4 - side a = height above ground to the roof edge.
Angle A = 180 - (23 + 90) = 82 degrees
sin 82 = op/hyp = a/c = a/75
0.9903 = a/75
a = 74 cm
5.4 m /100 = 540 cm
540 cm - 74 cm = 466 cm
466 cm = height above ground to roof edge