3 16 
Explanation
 Factor the numerator and denominator and cancel the common factors.
        
             
        
        
        
Answer: She ordered 4 toppings.
Step-by-step explanation:
Given: Total cost of pizza  = $ 12.90
Cost of pizza =$7.50
Price per topping = $1.35
Let x = Number of toppings, 
Total cost of pizza = (Cost of pizza) + (price per topping) × (Number of topping)  

hence, she ordered 4 toppings.
 
        
             
        
        
        
It's  <em>370,000.00000...</em>  with as many zeros as you want after the decimal point.
        
                    
             
        
        
        
Not quite sure what the question being asked here is.
        
             
        
        
        
Por determinante:
5...1...1
1...0...1 = 0 --> se o determinante for igual a 0, os pontos estarão alinhados.
3...3...1
calculando: (5 x 0 x 1 + 1 x 1 x 3 + 1 x 3 x 1) - (1 x 0 x 3 + 1 x 1 x 1 + 3 x 1 x 5) = 
0 + 3 + 3 - 0 - 1 - 15 = 
6 - 1 - 15 = 
5 - 15 = - 10 --> como não deu zero, os pontos não estão alinhados.