Question

A ladder leans against a vertical wall of

height 5 m. If the foot of the ladder is
12 m away from the wall, calculate
the length of the ladder.​

Answer 1

Answer: 13m

Explanation:

Use Pythagorean theorem: a²+b²=c²

5²+12²=c²

25+144=c²

c²=169

c=13 (even if it is true that there are positive and negative solution, but length cannot be negative)

Answer 2

Given:

• A ladder is leant against a wall of height 5m.
• The foot of ladder is 12m away from the wall.

To Find:

• The length of ladder.

Concept Used:

• We will use Pythagoras Theorem.

Answer:

Here given

• Vertical height = 5m.
• Base = 12m.

Here the length of ladder is equal to hypotenuse of ∆ so formed.

Now in a right angled ∆ ,

=> (hypotenuse)² = (pependicular)²+(base)².

=> h ² = (12m)²+(5m)²

=> h² = 144m² + 25m².

=> h² = 169m².

=> h = √169m².

=> h = 13m.

Hence the required answer is 13m.