Each leg of a [tex]$45^{\circ}-45^{\circ}-90^{\circ}$[/tex] triangle measures 14 cm. What is the length of the hypotenuse?

A. 7 cm

B. [tex]$7 \sqrt{2}$[/tex] cm

C. 14 cm

D. [tex]$14 \sqrt{2}$[/tex] cm



Answer :

In a [tex]\(45^\circ-45^\circ-90^\circ\)[/tex] triangle, the two legs are equal in length, and the relationship between the legs and the hypotenuse follows the ratio [tex]\(1:1:\sqrt{2}\)[/tex]. This means that if the length of each leg is [tex]\(14\)[/tex] cm, the hypotenuse ([tex]\(c\)[/tex]) can be found by multiplying the leg length by [tex]\(\sqrt{2}\)[/tex].

Here's the step-by-step process to determine the length of the hypotenuse:

1. Identify the length of the legs: Each leg of the triangle is [tex]\(14\)[/tex] cm.
2. Understand the relationship in a [tex]\(45^\circ-45^\circ-90^\circ\)[/tex] triangle: The hypotenuse is equal to the leg length times [tex]\(\sqrt{2}\)[/tex].

[tex]\[ \text{Hypotenuse} = \text{leg length} \times \sqrt{2} \][/tex]

3. Substitute the given leg length into the formula:

[tex]\[ \text{Hypotenuse} = 14 \, \text{cm} \times \sqrt{2} \][/tex]

4. Calculate the numerical value:

[tex]\[ 14 \times \sqrt{2} \approx 19.79898987322333 \, \text{cm} \][/tex]

Therefore, the length of the hypotenuse is approximately [tex]\(19.8\)[/tex] cm, rounded to one decimal place. So, the correct choice from the given options is:

[tex]\[ 14 \sqrt{2} \, \text{cm} \][/tex]