I don't think when this number is added to any other rational number would produce an irrational number
But we do know that when 0.4 is added to an irrational number it would be irrational. 
e.g; 0.4 + pi is irrational, etc, etc
So any other irrational number would make it irrational
        
             
        
        
        
Expanded: 8.000 + .500 + .010 + .007
Word Form: eight ones, five tenths, one hundredth, seven thousandths 
Hope this helps! 
        
             
        
        
        
Triangle A
hypotenuse: 3y + x
leg: y - x
Triangle B
hypotenuse: y + 5
leg: x + 5
Congruency => 3y + x = y + 5 and y - x = x + 5
Solve the system
3y + x = y + 5 -> 2y + x = 5
y - x = x + 5 -> y - 2x = 5
  2y + x = 5
-2y + 4x = -10
5x = -5
x = -1
y = (5 -(-1)) / 2 = 6/2 = 3
Verify:
 hypotenuses
3y + x = 9 - 1 = 8
y + 5 = 3 + 5 = 8
Legs:
y - x = 3 -(-1) = 3 + 1 = 4
x + 5 = -1 + 5 = 4.
Then both hypotenuses and both legs are congruent.
Answer: x = -1 and y = 3
        
             
        
        
        
Answer:
B. y-1=3(x-5)
Step-by-step explanation:
y=_+_(x-_)
y=1+(-3)(x-5)
y-1=3(x-5)
 
        
             
        
        
        
Its the first one, (-8,8) (2,2)