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

5 0

4 years ago

What is the domain of the function shown in the mapping?

Sergeeva-Olga [200]

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.

7 0

3 years ago

The equation y 16t 2 18t 405 describes the height in feet of a ball thrown downward at 18 feet per second from a height of 405 f

kumpel [21]

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

$-1 \times (16t^2 +18t -405)$

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 $(81\times 5, 27 \times 15, 9 \times 45).$

$(16t^2 +18t -405) = (8t + 45) (2t - 9)$

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

3 0

4 years ago