Let’s solve this step by step.
We’re told:
- The basketball goal is 40 ft tall → that’s the vertical side (opposite).
- Its shadow is 20 ft long → that’s the horizontal side (adjacent).
- We want to find the angle from the ground up to the top of the goal — that’s the angle we’d shoot at if we were standing at the end of the shadow and aiming for the top of the goal.
This forms a right triangle:
- Opposite = 40 ft
- Adjacent = 20 ft
- Angle x is between the adjacent side (ground) and the hypotenuse (line of sight/shoot path).
To find the angle when you know opposite and adjacent, use tangent:
> tan(x) = opposite / adjacent
> tan(x) = 40 / 20
> tan(x) = 2
Now, to find the angle whose tangent is 2, we use the inverse tangent function:
> x = tan⁻¹(2)
Using a calculator (make sure it’s in degree mode):
> tan⁻¹(2) ≈ 63.4349...°
Rounded to one decimal place:
63.4°
✔ Double-check:
If tan(x) = 2, then x should be more than 45° (since tan(45°)=1), and less than 90°. 63.4° makes sense.
Final Answer:
63.4°
Parent Tip: Review the logic above to help your child master the concept of trigonometry word problems worksheet with answers.