X=5. y=35. 
To solve, substitute the 7x into the equation for y. Solve. You get x=5. Then put that into your first equation. Solve. You get y=35. Hope that helps!!
        
             
        
        
        
16x^4-81y^4  difference of perfect squares...
(4x^2-9y^2)(4x^2+9y^2)  that's one of the equivalents...
(2x+3y)(2x-3y)(4x^2+9y^2)  that's another one of them...
        
             
        
        
        
Answer:

Step-by-step explanation:

 
        
             
        
        
        
(c/ b * 0) is just (c/0) and you cannot divide by 0 
 
        
             
        
        
        
Answer:
x
Step-by-step explanation:
 f(x)=2x+5
Input: x
Output: f(x)
For i.e:
Input: 1
Output: f(1) = 2(1) + 5 = 2 + 5 = 7