Answer: Choice B) The expression (10-2x)(30-2x)x represents the volume of the box
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The original width is 10 inches. The width reduces to 10-2x inches after we cut off the top two corners of the rectangle. We can think of it as taking 10 and subtracting off two copies of x like so: 10-x-x = 10-2x
Similarly, the length goes from 30 inches to 30-2x inches. This time we're taking off the top and bottom corners (focus on either side it doesn't matter).
The height of the box is x inches due to this portion being folded up.
Volume of box = (width)*(length)*(height)
Volume of box = (10-2x)(30-2x)x
Note: the units for the answer are in cubic inches which can be written as "in^3" (inches cubed).
Answer to the 1st question: 8 years
Answer to the 2nd question: The year 2022
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Further explanation:
x = number of years after 2008
y = average price of a new car
The prices are going up by $1250 per year on average. This is the slope because the slope is the rate of change. So m = 1250.
The y intercept is b = 30100 as this is the price in 2008.
This leads us to go from y = mx+b to y = 1250x+30100
Plug in x = 0 and you should get y = 30100.
Also, plugging x = 6 into the equation leads to y = 37600 to help confirm things.
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Next, we plug in y = 47600 and solve for x.
y = 1250x+30100
47600 = 1250x+30100
47600-30100 = 1250x
17500 = 1250x
1250x = 17500
x = 17500/1250
x = 14
This means 14 years after the year 2008 is when the average new car price will be $47,600.
2008+14 = 2022
2022-2014 = 8
Therefore, <u>8 years</u> after 2014 (aka the <u>the year 2022</u>) is when the new car average price will be $47,600.
The final answer is
y = -2x - 6
Many fractions including 1/5, 2/10, 3/15, 4/20 and up.
