A 30-foot ladder leans against a wall, forming a $76^{\circ}$ angle with the ground. We need to find the height the ladder reaches on the wall, rounded to the nearest tenth of a foot.
2025/4/2
1. Problem Description
A 30-foot ladder leans against a wall, forming a angle with the ground. We need to find the height the ladder reaches on the wall, rounded to the nearest tenth of a foot.
2. Solution Steps
Let be the height the ladder reaches on the wall. We have a right triangle where the ladder is the hypotenuse (30 feet), the angle between the ladder and the ground is , and the height the ladder reaches on the wall is the opposite side to the angle. We can use the sine function to relate these quantities:
In this case, , the opposite side is , and the hypotenuse is
3
0. So we have:
Multiplying both sides by 30, we get:
Using a calculator, we find that
Therefore,
Rounding to the nearest tenth of a foot, we get feet.
3. Final Answer
The ladder reaches approximately 29.1 feet on the wall.