Answer:
1. x=8 2. x=
Step-by-step explanation:
1. 17^2-15^2= 64
=8
x=8
sorry i only know 1 
 
        
             
        
        
        
Observe that

In the original equation, divide both sides by  :
:


Next,

where  is any integer. Then
 is any integer. Then

Fix  to ensure
 to ensure  , so that
, so that

 
        
             
        
        
        
Answer:
Option 1
Step-by-step explanation:
Remember that range is the x values or the input. So in this case the inputs {0, 1, 2, 3} are all matching the ones in option one!
Hope this helps and have a great day! 
 
        
             
        
        
        
X*y=72
x = 5y-2
x=72/y
72/y=5y-2
72=5y^2-2y
5y^2 -2y - 72 = 0
(5y+18)(y-4)=0
y = -18/5 discard
or y = 4
4x=72
x=18
(18,4)