Can someone help me please?

157.787 cubic cm

Step-by-step explanation:

Given: 8.3 cm

Assuming all sides are equal you have a LWH of 8.3 cubed. So 8.3 times 8.3 times 8.3

This gives you an area of 157.787 cm cubed round to the desired decimal or keep it if not directed otherwise.

Step-by-step explanation:

The area of a triangle is given by

where

b is the base

h is the height

Here we have an equilateral triangle, which has the 3 sides of the same length.

Let's call L the length of one side.

We know that the perimeter of the triangle is

p = 9 in

The perimeter is the sum of the three sides, so:

Therefore, we find the length of the side:

Therefore the length is the base of the triangle,

The height can be calculated by considering half triangle: the hypothenuse is equal to L, while one side is equal to half the base (b/2), therefore the height is given by Pythagorean's theorem:

Therefore, the area of the triangle is: