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The area of a rectangular room is 750 square feet. The width of the room is 5 feet less than the length of the room. Which equations can be used to solve for y, the length of the room? Select three options. y(y + 5) = 750 y2 – 5y = 750 750 – y(y – 5) = 0 y(y – 5) + 750 = 0 (y + 25)(y – 30) = 0

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With the given information, we can know that the area is 750 square feet.

The length we can set as y, meaning the width would be (y-5).

So, from these equations, which are the correct ones?

1. y(y+5) = 750
This not correct, as it should be a minus sign instead of addition.

2. y^2-5y = 750
This is correct, because when we do the normal area calculation, y^2-5y is what you would get if you do y(y-5).

3. 750 - y(y-5) = 0
This is correct, the total area minus the calculation of the total area would be 0.

4. y(y-5) + 750 = 0
This is not correct, because this is an area calculation it's impossible to get a negative. So it would not work.

5. (y+25)(y-30) = 0
This is correct. Once you simplify it, it becomes y^2 - 5y - 750 = 0. And then we can move the -750 over so it becomes a positive.


Hope this helped! <3
User Fahim Bagar
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