Kindly provide me example of problem solving on special products and factoring

Sagot :

Alden is three years older than Yaya Dub.  The product of their ages is 460.  Determine their ages.  
Let       x       age of Yaya Dub      
           x + 3  age of Alden
       
          460     product of their ages
 
Equation:               
(x) (x + 3) = 460
           
x² + 3x = 460
           
x² + 3x - 460 = 0     Product (Special Product/Quadratic Trinomial)
 

Solve by factoring:            
(x - 20) (x+23) = 0     Factor
 
Solve for x:              
x-20 = 0                   x+23 = 0
                
x1 = 20                     x2 = -23
 

Choose the positive x-value:       x1 = 20  
Determine their ages:  Substitute 20 for x             
Age of Yaya Dub:    x = 20              Age of Alden:  x + 3       
                                                                         (20) + 3 = 23