I believe your answer is 6 seconds.
Because the height of the ball = -16(x² - 5x - 6), when the height of the ball is 0, which is when it is on the ground, we can set -16(x² - 5x - 6) equal to 0. This also allows us to divide by -16, and then we can solve the equation:
x² - 5x - 6 = 0
(x - 6)(x + 1) = 0
So x = 6 or x = -1, and because a quantity of time cannot be negative, x would have to be 6, which means it takes 6 seconds for the ball to reach 0 feet.
I hope this helps!
        
             
        
        
        
Answer:31.9
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
Option C: 6(7 * 7)
Step-by-step explanation:
There are six faces of the cube. Since each face is 7 by 7 units, there are 6(7 *7) units total.
 
        
                    
             
        
        
        
The area of a parallelogram is equal to the base multiplied by the height. So in this instance it would be (3x+5)*(7x-1). Foil out the binomials. 21x^2+35x-3x-5 Combine like terms. 21x^2+32x-5
The area is 21x^2+32x-5
        
             
        
        
        
Answer:
   ≈ 58
Step-by-step explanation:
Estimation usually means you want an answer good to one or maybe two significant figures. That usually means you want to round the numbers involved to one or two significant figures.
Doing that here transforms the problem to 180/3 = 60, an answer with one significant figure. 
You can improve the estimate a bit by recognizing that it is a little high (the numerator is higher than 175.32, but the denominator is the same). Since the numerator is high by about 5, the estimate is high by about 5/3 or a little less than 2. A closer estimate will be 60 - 2 = 58.
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The degree to which you refine the estimate will depend on the error requirements you have. Certainly an estimate of 60 is within 10% of the true value, so is "close enough" for many purposes.