Answer:
I need a picture of the prism, then I will answer the question.
Step-by-step explanation:
 
        
             
        
        
        
<h3>
Answer:   20 sides</h3>
==================================================
Work Shown:
x = exterior angle
9x = interior angle
interior + exterior = 180
9x+x = 180
10x = 180
x = 180/10
x = 18
n = number of sides
n = 360/x
n = 360/18
n = 20
There are <u>20</u> sides to the regular polygon.
Side notes: 
- The formula to determine n only works for regular polygons.
- A polygon with 20 sides is known as an icosagon.
- Any pair of adjacent interior and exterior angles are supplementary. They add to 180 degrees.
 
        
        
        
Answer:
Just #1
Step-by-step explanation:
 
        
             
        
        
        
Answer:
75
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
- Multiplication Property of Equality
- Division Property of Equality
- Addition Property of Equality
- Subtraction Property of Equality<u>
</u>
<u>Geometry</u>
- Sum of Angles in a Quadrilateral: 360
Step-by-step explanation:
<u>Step 1: Set up</u>
75 + 120 + 90 + ∠4 = 360
<u>Step 2: Solve</u>
- Add:                                                                                                                   285 + ∠4 = 360
- [Subtraction Property of Equality] Subtract 285 on both sides:                   ∠4 = 75
 
        
             
        
        
        
Answer:
$31.05
Step-by-step explanation:
8% of 25 is 2 
25 + 2 = 27
15% of 27 is 4.05
27 + 4.05 = 31.05
$31.05 is how much she spends