The height of a wall is 4 m and a ladder is placed at a distance of 3 m from the wall. Find the length of the ladder.

Correct answer: 5. The ladder is the hypotenuse: √(3² + 4²) = √25 = 5 m.

Background: Use the Pythagorean theorem: a² + b² = c².

• 4: 4 m is the height of the wall, not the ladder.
• 3: 3 m is the distance from the wall, not the ladder.
• 2: 2 m is shorter than both sides of the triangle.

Did you know? 3-4-5 is a common Pythagorean triple.

Memory trick: 3-4-5 triangle.