Question

what is the perimeter of a triangle with sides 15 inches, 15 inches and 21 inches in length?
15
15
21
a 30 inches
b 36 inches
c 51 inches
d 53 inches

Explanation:

Step1: Recall perimeter formula for triangle

The perimeter \( P \) of a triangle is the sum of the lengths of its three sides. So, \( P = a + b + c \), where \( a \), \( b \), and \( c \) are the side lengths.

Step2: Substitute the given side lengths

Here, \( a = 15 \) inches, \( b = 15 \) inches, and \( c = 21 \) inches. Substituting these values into the formula: \( P = 15 + 15 + 21 \).

Step3: Calculate the sum

First, add \( 15 + 15 = 30 \). Then, add \( 30 + 21 = 51 \).

Answer:

C. 51 inches