(1,35)(2,60)(3,92)(4,120)(5,175)
        
             
        
        
        
Multiply both sides of the second equation by 4. That will give you -4x in the second equation which when added to 4x of the first equation will eliminate x.
Second equation:
-x + 3y = 6
Multiply the second equation by 4 on both sides:
-4x + 12y = 26
        
             
        
        
        
Answer:
Four (4) pounds
Step-by-step explanation:
Because we required two (2) pounds to stretch the spring eight (8) inches, we need double the force to stretch it sixteen (16) inches. Sixteen is just double the original amount, meaning we need four (4) pounds to stretch the spring sixteen inches. 
Hope this helps!
 
        
             
        
        
        
The answer to this question is y = –3x^2, just had this on e2020 :)