Precalculus solving right triangles worksheet
In Precalculus right triangles are the base for the trig functions, and the problems are mostly applications: angles of elevation and depression, heights and distances. Draw the picture and mark the right angle before choosing a ratio.
Also taught in Geometry and Algebra 2, each at its own level and with its own examples.
Select your difficulty
Pick more than one for a sheet that mixes them.
The preview can look cramped on a phone. The PDF and printed sheet come out normal.
Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep
Sigma Prep · sigmaprep.io/worksheets Name Solving Right TrianglesDate Period Find each measure.
Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep |
Sigma Prep · sigmaprep.io/worksheets Name Solving Right TrianglesAnswer keyVersion 1Date Period Find each measure.
Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep |
How to do these
From 50 m away, the angle of elevation to the top of a tower is . Find its height
- The 50 m is adjacent to the angle and the height is opposite, so use tangent.
- h = 50 tan 38°.
- 50 × 0.7813 = 39.06.
The answer is m.
Where students go wrong
Measuring an angle of depression from the vertical. It is measured down from the horizontal, so it equals the angle of elevation from the other end.
Also called finding missing angles or inverse trig ratios.
What you can put on this worksheet
- A missing side, any angle, rounded
- Find . Round to the nearest tenth. — a right triangle with a 47° angle, legs 13 and x, hypotenuse unknown →
- An angle from two sides, with inverse trig
- Find . Round to the nearest degree. — a right triangle with a θ angle, legs 20 and 13, hypotenuse unknown →
- The acute angles, exactly
- A right triangle has legs and . Find the larger acute angle →
- Solve the whole triangle
- Solve right triangle with , , . Round sides to the nearest tenth. → , ,
- All three sides given: find the angle
- Find to the nearest tenth of a degree — a right triangle with base 63, height 60 and hypotenuse 87 →
- Triangles drawn any way round
- Find to the nearest tenth — a right triangle, labeled 39, x, 48°, D, E, F →
- The altitude splits it into two right triangles
- Find to the nearest tenth — a triangle split into two right triangles by its altitude, labeled x, 32, 54°, 55° →