In quadrilateral ABCD, BC is parallel to AD. E is the foot of the perpendicular from B to AD. Find BE, if AB = 17cm, BC = 16cm, CD = 25cm and AD = 44cm.
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Draw a rough sketch to visualize the problem. Drop a perp from c to the base in f. Now be and cf both are altitudes of same height.
From the 2 right triangles formed you can write an equation
25²– x² = 17² - (28-x)²
solving we get x = 20
now see triangle BAE and solve for BE
BE² = 17² - 8²
BE = 15
From the 2 right triangles formed you can write an equation
25²– x² = 17² - (28-x)²
solving we get x = 20
now see triangle BAE and solve for BE
BE² = 17² - 8²
BE = 15
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Draw a picture of the quadrilateral and then first give a try yourself. Otherwise you will never learn.