I am assuming you wrote the problem wrong. Is it a^2?
A^2 -4A-21=0
(A-7)(A+3)=0
A=7 A=-3, ignore the negative number because it doesn't make sense if you plug in for a.
length=a+3=7+3=10
Width=7=a
        
             
        
        
        
Answer:
A.) x-y=2 and x+2y=-2
Step-by-step explanation:
For option A, we have:
x-y=2 
 x+2y=-2
Subtract the first equation from the second, to get:
2y--y=-2-2
This implies that:
2y+y=-2-2
Simplify to get:
3y=-4
Divide both sides by 3 to get:

We substitute y=-1.3 into the first equation to get:
x--1.3=2
x+1.3=2
x=2-1.3
x=0.7
The solution is (0.7,-1.3), which is approximately (0.7, -1.4)
By inspection, all the other factors have solutions not close to (0.7, -1.4)
 
        
                    
             
        
        
        
For every value tht x increases, y decreases by 3
-3x
Then to find the y intercept, look at 0's corresponding value (8)
-3x+8
        
             
        
        
        
Answer:
Option B
Step-by-step explanation:
Given:
As per the contract "Notification of the Buyer’s intent to do so must be made by written letter or phone call to the phone number and address listed below within one business week of delinquency.”
So,buyer needs to only notify the bank about the monthly payments in case of delinquency and not about if payment is going to be late or not. 
Option B is correct
Notify the bank if a payment is going to be late !
 
        
             
        
        
        
(1, -6) and (-5, 2)
Distance between 1 and -5 = 6
Distance between -6 and 2 = 8
6²+8²=x² (PYTHAGOREAN THEOREM)
36+64=x²
x² = 100
x = 10
Note: Not -10 because <em>distance cannot be negative.</em>