Check the picture below.
notice chord QR is a diameter, thus the vertex at P has a right-angle by Thales theorem.
 
        
             
        
        
        
Vas happenin!!
19. TX
20. O and I can’t see the other bottom of the cube 
21. WS
Hope this helps *smiles* 
Sorry if it’s wrong
        
             
        
        
        
<span>3x + y = 9 (I)
</span><span>y = –4x + 10 (II)
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Pass the incognito "4x" to the first term, changing the signal when changing sides.
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simplify by (-1)
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<span><span>
</span></span><span>Substitute in equation (I) to find the value of "Y".
</span>3x + y = 9 (I)
3*(1) + y = 9
3 + y = 9
y = 9 - 3

Answer:

 
        
        
        
The surface area of a rectangular prism is given by
... S = 2(LW +H(L+W))
For your dimensions, the surface area is
... S = 2(3·1 + 2(3+1)) = 2(3 + 8) = 22 . . . ft²
 
        
             
        
        
        
The width is 11.
You can get this by setting up an equation that says:
x (x - 3) = 154
Then distribute and use the quadratic equation to solve.