Answer:
 son = 10 , father = 40 
Step-by-step explanation:
Let Five years ago the age of son be x years and age of father be 7x years
Present age of son =x+5
Present age of father =7x+5
5 years later their age will (x+10) and (7x+10)
∴7x+10=3(x+10)
7x−3x=20
4x=20
x=5
So, the present age of son=x+5=5+5=10years
and the present age of father=7x+5=35+5=40years
hope it helps you
 
        
             
        
        
        
Answer: 
Maximum area possible
 f(max)  = 3906,25 ft²
Dimensions:
a  = 62,5  ft
w  = 62,5 ft
Step-by-step explanation:
Perimeter of the rectangular fencing    P  =  250 feet
And sides of the rectangle  a  and  w (width of rectangle)
Then
A =  a*w
2a  + 2w  = 250       ⇒  a  =  (250 -2w)/ 2    ⇒  a = 125 - w
f(w)  =  (125  - w ) *w        f(w)  = 125w - w²  
Taking derivatives both sides of the equation
f´(w)   =  125  - 2w              f´(w)   = 0           125  - 2w = 0
w = 125/2
w = 62,5 ft            ⇒  a = 125 - 62,5
 a = 62,5 ft
f(max)  = ( 62,5)²
f(max)  = 3906,25 ft²
 
        
             
        
        
        
Answer:
equivalent
Step-by-step explanation:
when you divide the second one by 2 you'll get the first one