The perimeter of a rectangle olis 40 inches. If the length of the rectangle is 13 inches, which equation could be used to find the width of x
The width is 7
Answer: Choice A
The domain is the set {-5, -3, 1, 2, 6} which can be written as {x| x=-5, -3, 1, 2, 6} if you want to make it clear that x is involved with the domain.
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Explanation:
The domain is the set of x values, or the set of inputs, of a function or relation. All you have to do is list off the values in the "input" oval. Those values from top to bottom are: -3, 2, -5, 1, 6. Sort them out from smallest to largest and you get -5, -3, 1, 2, 6 which points us to choice A.
Another route you could go is eliminating choices B, C and D because -9 is not in the "input" oval.
Answer:
Ball hits the ground after 4.5 sec
Step-by-step explanation:
Let a -1, so that the leading coefficient is positive
So our quadratic is

The key coefficients of two binomial variables can be 1 and 16, or 2 and 8, or 4 and 4, for the leading coefficient of 16.
Yet they can't actually be 4 and 4 because the linear (x) term coefficient has to be a multiple of 4, which it isn't and leading coefficients 1 and 16 on the binomial factors is not likely.
So, 2 and 8 taken as the leading coefficients of two binomial factors.
For constant 405, possible factorizations are 

Taking first factor, thus we find negative value for given time t. But second time equivalent to zero gives the value of 4.5 for t
Thus ball hits the ground after 4.5 sec
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