document.write( "Question 1187826: https://imgur.com/8J0Mleu ABCD is a trapezoid with AD ||BC. If AD = 5 cm and BC = 11 cm, and if the area of the trapezoid is 80 cm^2, find the area of triangle ABE, in cm^2. \n" ); document.write( "
Algebra.Com's Answer #818833 by MathLover1(20849)\"\" \"About 
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\n" ); document.write( "With \"AD\" parallel to \"BC\" and \"E\" the midpoint of \"CD\", the area of triangle \"ABE\" is \"half\" the area of the trapezoid.\r
\n" ); document.write( "\n" ); document.write( "ANSWER: The area of triangle ABE is \"166cm%5E2%2F2+=+83cm%5E2\".\r
\n" ); document.write( "\n" ); document.write( "To see that this is true, consider the midline \"EF\" of the trapezoid.\r
\n" ); document.write( "\n" ); document.write( "Let the height of the trapezoid be \"2x\"; then the altitudes of triangles \"ADE\",\"+AFE\", \"BFE\", and \"BEC\" are all\"+x\".\r
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\n" ); document.write( "\n" ); document.write( "The area of triangle \"ABE\" is the sum of the areas of triangles \"AFE\" and \"BFE\":\r
\n" ); document.write( "\n" ); document.write( "\"%281%2F2%29%2811%29%28x%29%2B%281%2F2%29%2811%29%28x%29+=+11x\"\r
\n" ); document.write( "\n" ); document.write( "The area of the trapezoid is\r
\n" ); document.write( "\n" ); document.write( "\"%281%2F2%29%288%2B14%29%282x%29+=+22x\"\r
\n" ); document.write( "\n" ); document.write( "So the area of triangle \"ABE\" is \"half+\"the area of the trapezoid.\r
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