Subtract 3 from each side to isolate the x and you get x=y-3
For this case we have that by definition, the perimeter of the rectangle is given by:

Where:
W: Is the width of the rectangle
L: is the length of the rectangle
According to the data we have:

Substituting:

So, the width of the rectangle is 9 inches

So, the length of the rectangle is 15 inches
Answer:
the width of the rectangle is 9 inches
the length of the rectangle is 15 inches
For question number 1:The plot H = H(t) is the parabola and it reaches its maximum in the moment when exactly at midpoint between the roots t = 0 and t = 23. At that moment t = 23/2 or 11.5 seconds.
For question number 2:To find the maximal height, just simply substitute t = 11.5 into the quadratic equation. The answer would be 22.9.
For question number 3:H(t) = 0, or, which is the same as -16t^2 + 368t = 0.Factor the left side to get -16*t*(t - 23) = 0.t = 0, relates to the very start of the process, when the ash started its way up.The other root is t = 23 seconds, and it is precisely the time moment when the bit of ash will go back to the ground.
Answer as a compound inequality: 
Answer in interval notation: [-4, 2)
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Explanation:
The range is the set of all possible y outputs of a function. When dealing with a graph like this, we just look at the highest and lowest points to determine which y values are possible.
The lowest point occurs when y = -4. We include this value. So far we have
which is the same as 
The upper ceiling for the y value is y = 2. We can't actually reach this value because of the open hole at (-3,2). So we say that 
Combine
and
to get the compound inequality 
This says y is between -4 and 2, including -4 but excluding 2.
To convert this to interval notation, we write [-4, 2) where the square bracket says to include the endpoint and the curved parenthesis says to exclude the endpoint.