Answer:
- 7 faces
- 15 edges
- 10 vertices
Step-by-step explanation:
This is a counting problem. As with many counting problems, it is helpful to adopt a strategy that helps ensure you count everything only once.
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<h3>Faces</h3>
There are two pentagonal faces and 5 rectangular faces for a total of ...
7 faces
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<h3>Edges</h3>
There are 5 edges around each of the pentagonal faces, and 5 edges connecting the top face to the bottom faces, for a total of ...
15 edges
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<h3>Vertices</h3>
There are 5 vertices on the top face, and 5 on the bottom face, for a total of ...
10 vertices
The numbers are 11 and 6.
Hope this helps!!!
Given:
Equilateral triangle: height = 2.6 inches ; base or side length = 3 inches
Rectangle: length = 6 inches ; width = 3 inches
1 name plate has 2 equilateral triangle and 3 rectangles.
Surface area of an equilateral triangle = √3/4 * a² = √3/4 * 3² = 3.9 in²
3.9 in² x 2 = 7.8 in²
Surface area of a rectangle = 6 in * 3 in = 18 in²
18 in² x 3 = 54 in²
7.8 in² + 54 in² = 61.8 in²
61.8 in² x 30 nameplates = 1,854 in² Choice A.
Hello!
To find the side length you use the equation

a is side length
d is diagonal
Put in the number we know

Divide

Multiply
a = 19.091
The answer is 19.09
Hope this helps!
The error is in the second step they subtracted 3 from both sides but it was a 3x, which you can not do.
Correction.
9x+18+3x=1
12x+18=1
12x=-17
x=-17/12