document.write( "Question 123463: May I please have some help finding the area?\r
\n" ); document.write( "\n" ); document.write( "Draw the parallelogram with vertices A(8, 5), B(17, 5), C(12, 10), and D(21, 10) on a coordinate plane. Find the area of the rectangle
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Algebra.Com's Answer #90602 by solver91311(24713)\"\" \"About 
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\n" ); document.write( "Discussion
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\n" ); document.write( "You wrote:
\n" ); document.write( "\"Draw the parallelogram with vertices A(8, 5), B(17, 5), C(12, 10), and
\n" ); document.write( "D(21, 10) on a coordinate plane. Find the area of the rectangle.\"\r
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\n" ); document.write( "\n" ); document.write( "Here's the diagram:\r
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\n" ); document.write( "\n" ); document.write( "Try as I might, I can't find a rectangle. So I'll just assume you want the
\n" ); document.write( "area of the parallelogram.\r
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\n" ); document.write( "\n" ); document.write( "The area of a parallelogram is given by \"A=bh\" where b is the measure of
\n" ); document.write( "the base and h is the measure of the height.\r
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\n" ); document.write( "Solution
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\n" ); document.write( "Since the base of this parallelogram is parallel to the x-axis, the measure of
\n" ); document.write( "the base is calculated by the difference in the x-coordinates of the end
\n" ); document.write( "points of the base line segment. \"b=17-8=red%289%29\"\r
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\n" ); document.write( "\n" ); document.write( "Note: You could use the distance formula to calculate the measure of the base,
\n" ); document.write( "but since the y-coordinates of the two points are equal, the distance formula
\n" ); document.write( "degenerates to the square root of the square of the difference in x, or simply
\n" ); document.write( "the difference in x.\r
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\n" ); document.write( "\n" ); document.write( "Also, the height is parallel to the y-axis, so the measure of the height is
\n" ); document.write( "calculated by the difference in the y-coordinates of the end points of the
\n" ); document.write( "height line segment. One of the end points is given and has a y-coordinate of
\n" ); document.write( "10. But the other point is not given. Fortunately, the missing end point
\n" ); document.write( "lies on the line segment representing the base. Since that line segment is
\n" ); document.write( "parallel to the x-axis, all of the points on that line have the same
\n" ); document.write( "y-coordinate. Therefore, the y-coordinate of the missing end point of the
\n" ); document.write( "height line segment is equal to the y-coordinate of either end point of the
\n" ); document.write( "base line segment, namely 5. Hence, the measure of the height is \"10-5=green%285%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now we have sufficient information to calculate the area of the parallelogram:\r
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\n" ); document.write( "\n" ); document.write( "\"A%5Bp%5D=b%2Ah=red%289%29%2Agreen%285%29=blue%2845%29\" square units.\r
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\n" ); document.write( "Check Answer
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\n" ); document.write( "Cut off the triangle that was formed on the left of the parallelogram by the
\n" ); document.write( "construction of the height line segment. Move this triangle to the left side
\n" ); document.write( "of the parallelogram to form a 9 unit by 5 unit rectangle. Multiply 9 times 5
\n" ); document.write( "to get 45 which is the area of the rectangle equal to the area of the
\n" ); document.write( "parallelogram. Alternatively, you could count the grid squares contained in
\n" ); document.write( "the rectangle to verify there are 45 of them.
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