GeometryFormula

Right Triangle Practice Problems

15 right triangle problems with full worked solutions, graded from warm-up to stretch — plus an unlimited supply you can generate yourself. Every answer is computed by the same verified function that powers the right triangle explorer, so the solutions cannot disagree with the formulas. Free, no account, nothing to install.

Formulas you need

  • Hypotenuse: c=a2+b2c = \sqrt{a^2 + b^2}
  • Area: A=12abA = \tfrac{1}{2} a b
  • Perimeter: P=a+b+cP = a + b + c

where a, b = the two legs, c = hypotenuse (longest side), A = area

Generate a new problem

Pick a difficulty, work it out, then check your answer. Every press gives a new question — the numbers are drawn fresh each time, so you can keep going.

Warm-up

  1. A right triangle has leg a = 4 and leg b = 6. Find the hypotenuse (c).

    Answer & working

    7.21 units

    c = √(a² + b²) = √(16 + 36) ≈ 7.21

  2. A right triangle has leg a = 6 and leg b = 5. Find the area (A).

    Answer & working

    15 units²

    A = ½ · a · b = ½ · 6 · 5 = 15

  3. A right triangle has leg a = 1 and leg b = 5. Find the perimeter (P).

    Answer & working

    11.1 units

    P = a + b + c = 1 + 5 + 5.099 ≈ 11.1

  4. A right triangle has leg a = 5 and leg b = 5. Find the hypotenuse (c).

    Answer & working

    7.07 units

    c = √(a² + b²) = √(25 + 25) ≈ 7.07

  5. A right triangle has leg a = 1 and leg b = 4. Find the area (A).

    Answer & working

    2 units²

    A = ½ · a · b = ½ · 1 · 4 = 2

Core practice

  1. A right triangle has leg a = 5 and leg b = 7. Find the hypotenuse (c).

    Answer & working

    8.6 units

    c = √(a² + b²) = √(25 + 49) ≈ 8.6

  2. A right triangle has leg a = 8 and leg b = 4. Find the area (A).

    Answer & working

    16 units²

    A = ½ · a · b = ½ · 8 · 4 = 16

  3. A right triangle has leg a = 1 and leg b = 4. Find the perimeter (P).

    Answer & working

    9.12 units

    P = a + b + c = 1 + 4 + 4.1231 ≈ 9.12

  4. A right triangle has leg a = 11 and leg b = 9. Find the hypotenuse (c).

    Answer & working

    14.21 units

    c = √(a² + b²) = √(121 + 81) ≈ 14.21

  5. A right triangle has leg a = 10 and leg b = 11. Find the area (A).

    Answer & working

    55 units²

    A = ½ · a · b = ½ · 10 · 11 = 55

Stretch

  1. A right triangle has leg a = 11.5 and leg b = 2.5. Find the hypotenuse (c).

    Answer & working

    11.77 units

    c = √(a² + b²) = √(132.25 + 6.25) ≈ 11.77

  2. A right triangle has leg a = 6.5 and leg b = 8.5. Find the area (A).

    Answer & working

    27.63 units²

    A = ½ · a · b = ½ · 6.5 · 8.5 ≈ 27.63

  3. A right triangle has leg a = 2.5 and leg b = 1.5. Find the perimeter (P).

    Answer & working

    6.92 units

    P = a + b + c = 2.5 + 1.5 + 2.9155 ≈ 6.92

  4. A right triangle has leg a = 5.5 and leg b = 2.5. Find the hypotenuse (c).

    Answer & working

    6.04 units

    c = √(a² + b²) = √(30.25 + 6.25) ≈ 6.04

  5. A right triangle has leg a = 5.5 and leg b = 11.5. Find the area (A).

    Answer & working

    31.63 units²

    A = ½ · a · b = ½ · 5.5 · 11.5 ≈ 31.63

Answers are recomputed from the verified right triangle function every time this page is built, and every printed line is checked to evaluate correctly. Content last reviewed August 2026. Found a mistake? Tell us — we correct and republish.

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