What is the area of the square with the following

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What is the area of the square with the following coordinates: (x, y), (20, 20), (20, 5), (x, 5)?

A. 60.
B. 85.
C. 125.
D. 225.
E. It cannot be determined from the information given

I couldn't solve this PS question. I think that the correct answer is the option E. Experts, can you help me? Thanks in advanced.

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by [email protected] » Fri Mar 09, 2018 12:55 pm
Hi M7MBA,

We're told that a SQUARE has the coordinates: (X, Y), (20, 20), (20, 5) and (X, 5). We're asked for the AREA of that square.

To start, you would likely find it useful to draw a quick sketch of what you know. You can graph the points (20,20) and (20,5). Those two co-ordinates COULD be the side of the square OR they could be the diagonal of the square, so a little more work is needed to know for sure. Consider the point (X, 5) along with those 2 co-ordinates. Wherever that third point is located, the angle created among those 3 points will create a RIGHT ANGLE since (X, 5) and (20,5) create a horizontal line and (20,5) and (20,20) create a vertical line. Thus, we now know that (20,20 and (20,5) represent one side of the square.

That side length is 20 - 5 = 15.

With that side length, we can answer the given question. The area of the square will be 15^2 = 225.

Final Answer: D

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