No it is not a function, because a function cannot have more than one output per input. When x=-3, there are two solutions shown: (-3,2) and (-3,3), therefore it cannot be a function.
        
             
        
        
        
Answer:
See below
Step-by-step explanation:
You know that he spent 1/3 of his earnings, and then 1/4. After this, he has $28.90. You can write the equation like this:
1/4(x * 1/3) = $28.90. 
If you need to solve it:
1/4 * 1/3x = 28.90
1/12x = 28.90 
x = 346.80
 
        
             
        
        
        
Hope you won't be turned off by a correction, but we really need to use the symbol " ^ " to denote exponentiation.
Thus, we have x^2 = 100
Taking the square root of both sides, we get x = plus or minus 10. Verify, please, that both x = -10 and x = +10 satisfy the given equation.
 
        
             
        
        
        
Answer:
the answer would be 1/225