Answer:
The answer is  .
.
Step-by-step explanation:
Given:
18 2/5 - n = -10 1/3.
Now, to solve the equation:

Converting the mixed fractions to improper:
⇒
Moving the numbers on one side and variable to the other:
⇒
Now, solving the factions:
⇒
⇒
⇒
⇒
Therefore, the answer is  .
.
 
        
             
        
        
        
Answer:
Step-by-step explanation:
<u>3 hours for studying x subjects:</u>
 
        
             
        
        
        
Answer:
Perimeter is 8x²y+26x
Area is 52x³y
Step-by-step explanation:
The perimeter is 2W+2L and area is LW
Perimeter:
2(4x²y)+2(13x)
8x²y+26x
Area:
(4x²y)(13x)
52x³y
 
        
             
        
        
        
Used show you have more than what is needed. Example is you need 6 slices of pizza for all your friends but have 7 slices you have more than is needed.
        
             
        
        
        
Answer:
x³ - 5x² + 81x - 405 = 0
Step-by-step explanation:
Complex roots occur in conjugate pairs.
Thus given x = - 9i is a root then x = 9i is also a root
The factors are then (x - 5), (x - 9i) and (x + 9i)
The polynomial is the the product of the roots, that is
f(x) = (x - 5)(x - 9i)(x + 9i) ← expand the complex factors
     = (x - 5)(x² - 81i²) → note i² = - 1
     = (x - 5)(x² + 81) ← distribute
     = x³ + 81x - 5x² - 405, thus
x³ - 5x² + 81x - 405 = 0 ← is the polynomial equation