# What is the perimeter of the right angle triangle given two sides 3 and 4 ?

justaguide | College Teacher | (Level 2) Distinguished Educator

Posted on

The triangle is given to be a right angled

triangle. Taking 3 and 4 as the lengths of the shorter sides, the length of the hypotenuse can be derived using the Pythagorean Theorem as sqrt ( 9 + 16) = sqrt 25 = 5

The lengths of the three sides are now 3, 4 and 5 .

If we add them, we get the perimeter as 3 + 4 + 5 = 12.

The required perimeter of the triangle is 12.

hala718 | High School Teacher | (Level 1) Educator Emeritus

Posted on

Given the right angle triangle with two sides 3 and 4

To find the perimeter first we will need to determine the length of the third side which is the hypotenuse.

We will use the formula to find the hypotenuse.

We know that if a and b are sides of a right angle triangle and c is the hypotenuse , then c^2 = a^2 + b^2

Let us substitute.

==> c^2 = 3^2+ 4^2

==> c^2 = 9 + 16 = 25

==> c = 5

Then the length of the third side is 5.

Now we will calculate the perimeter.

==> P = 3 + 4 + 5 = 12

Then the perimeter is 12 units.