Answer:
   $359.42
Step-by-step explanation:
The difference in the investment values can be computed by making use of the formulas for the account balance in each case.
   compound interest: A = P(1 +r)^t . . . . interest at rate r compounded annually
   simple interst: A = P(1 +rt) . . . . simple interest at rate r
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The account earning simple interest will have a balance of ...
   A = $8000(1 +0.12×3) = $10,880
The account earning compound interest will have a balance of ...
   A = $8000(1 +0.12)^3 ≈ $11,239.42
The difference between the two investments is ...
   $11,239.42 -10,880 = $359.42
 
        
             
        
        
        
Step-by-step explanation:
We can set up an average equation in the form, where x is the last score in the fourth quarter:


She needs at least a 95 on the last quarter to average 90 in all four quarters. 
 
        
             
        
        
        
8,020 divided by 10 is 802.
Hope this helps!
        
                    
             
        
        
        
Answer:
(-5, 2) and (2, 6)
Step-by-step explanation:
Use the substitution method. We know that y = 3x and y = x^2 - 10, so we can set them equal to one another.
3x = x^2 - 10
x^2 - 3x - 10 = 0
Use the quadratic equation to solve for x. 
x = - 5, 2
Now solve for y using these two values of x by substituting it back into the equations.
y = - 15,  6
In coordinate form, (-5, 2) and (2, 6)