2x-4(x+1)=-13
1) we solve this equation:
2x-4(x+1)=-12
2x-4x-4=-12
-2x=-12+4
-2x=-8
x=-8/-2
x=4
2) we evalute x²-1
x²-1=4²-1=16-1=15
Answer: 15
        
             
        
        
        
<h3>Given</h3>
4 hundreds flats; 5 tens rods; 2 ones cubes
<h3>Find</h3>
The number of hundreds flats in each of 2 equal piles
<h3>Solution</h3>
When 4 flats are divided into two equal groups, each group will have ...
... 2 flats
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You can imagine doing this the way a card dealer might: first put 1 flat in each of 2 piles, then do the same for the remaining 2 flats. Each pile will end up with 2 flats.
— — — — —
You will have a problem if you continue with the tens rods. There is an odd number of those, so one of them will have to be exchanged for 10 ones cubes.
 
        
             
        
        
        
Answer:
~Exponential decay because the base is less than 1~
Step-by-step explanation:
I just took the test and got a 100% :) hope this helped! Good luck! 
 
        
             
        
        
        
The answer would be 7x+ 17
        
             
        
        
        
Answer:
x = 4, -2 1/2
Step-by-step explanation:
factors:
(2x + 5) (x - 4)
set each factor equal to zero:
2x + 5 = 0
2x = -5
x = -5/2
x - 4 = 0
x = 4