76.7k views
3 votes
Gabriel makes a model of a pyramid with the dimensions shown. A square pyramid. The square base has side lengths of 12 inches. The triangular sides have a height of 11 inches. Gabriel wants to paint the model. How much paint will he need? The area of the square base is in.2. The area of each triangular face is in.2. Gabriel will need in.2 of paint.

User Dashton
by
4.1k points

2 Answers

6 votes

Answer:

The area of the square base is 144 in²

The area of each triangular face is 66 in²

Gabriel will need 408 in² of paint.

Explanation:

The area of the square base is:

12² = 144 in²

The area of each triangular face:

½(12×11) = 66 in²

Gabriel will need:

4(66) + 144 = 408 in²

User R Poon
by
4.5k points
6 votes

Answer:

Area of the square base: 144 in²

Area of each triangular face: 66 in²

Amount of paint needed: 408 in²

Explanation:

We basically want to find the surface area of this square pyramid.

First, find the areas of the 4 triangular sides. The area of a triangle is denoted by:
A=(1)/(2) bh, where b is the base and h is the height.

Here, the base coincides with the side length of the square, so b = 12. The height is 11, so h = 11. Plug these in:


A=(1)/(2) bh


A=(1)/(2) * 12 * 11 = 66 inches squared

Each triangular face is thus 66 inches squared.

Since there are 4 triangles, multiply 66 by 4: 66 * 4 = 264 inches squared

Now, find the area of the square base. The area of a square is: A = s * s, where s is the side length. Here, the side length is 12, so s = 12. Plug this into the equation:

A = s * s

A = 12 * 12 = 144

So, the square base is 144 inches squared.

Finally, add 144 to 264 to get the total area Gabriel needs to paint:

144 + 264 = 408 inches squared

User AlexArgus
by
4.0k points