Question

find the perimeter and area of the regular triangle (all sides are congruent). 5. 9.96 in. 11.5 in.

Explanation:

Step1: Find the perimeter

Since it's a regular triangle and one - side length is given as 11.5 in, and perimeter of a regular triangle $P = 3s$ (where $s$ is side - length).
$P=3\times11.5 = 34.5$ in

Step2: Find the area

The area formula for a triangle is $A=\frac{1}{2}bh$, where $b$ is the base and $h$ is the height. Here, $b = 11.5$ in and $h=9.96$ in.
$A=\frac{1}{2}\times11.5\times9.96$
$A = 11.5\times4.98=57.27$ in²

Answer:

Perimeter: 34.5 in, Area: 57.27 in²