Answer:
A and B, A and C
Step-by-step explanation:
A and B touch at T same as A and C. The tangent is in between the two circles but through the touching points. B and C share the tangent but externally since at T it does not pass in between them.
 
        
             
        
        
        
9/19 - 3/14
= 126/140 - 57/140
= 69/140
        
             
        
        
        
Answer:
infinite solution
Step-by-step explanation:
because it is a linear equation.
 
        
             
        
        
        
X = amount of the 18% solution
y = amount of the 40% solution
we know the 18% solution has only 18% of alcohol, the rest is maybe water or something, now, how many liters is 18%?  well, 18% of anything is just (18/100) * anything, so, 18% of x is just (18/100) *x or 0.18x, and that's how many liters are there.
likewise, how many liters are there in the 40% solution?  well, (40/100) * y, or 0.4y, that many.
we know the mixture has to yield 10 liters at 20% alcohol, how many liters of only alcohol is that?  well, (20/100) * 10, or 2 liters.


how much of the 40% solution?  well y = 10 - x
 
        
        
        
In fix fraction it will be, 1 7/8 
and the exact answer is 15/8
and in decimal from it will be, 1.875