document.write( "Question 981751: At a certain time of day, a tree that is x meters tall casts a shadow that is x-35 meters long if the distance from the top of the tree to the end of the shadow is x+5 meters long, what is the height, x, of the tree \n" ); document.write( "
Algebra.Com's Answer #602692 by Cromlix(4381)\"\" \"About 
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Hi there,
\n" ); document.write( "Consider the tree and its shadow
\n" ); document.write( "as a right angled triangle
\n" ); document.write( "The tree = 'x'
\n" ); document.write( "The shadow = x - 35
\n" ); document.write( "The distance from the top of the
\n" ); document.write( "tree to the end of the shadow
\n" ); document.write( "= x + 5
\n" ); document.write( "Using Pythagoras:
\n" ); document.write( "x^2 + (x - 35)^2 = (x + 5)^2
\n" ); document.write( "x^2 + x^2 - 70x + 1225 = x^2 + 10x + 25
\n" ); document.write( "Collect like terms
\n" ); document.write( "x^2 + x^2 - x^2 -70x - 10x + 1225 - 25 = 0
\n" ); document.write( "x^2 - 80x + 1200 = 0
\n" ); document.write( "Factorise
\n" ); document.write( "(x - 20)(x - 60) = 0
\n" ); document.write( "x - 20 = 0
\n" ); document.write( "x = 20 (No answer as side x - 35 would give a negative answer)
\n" ); document.write( "x - 60 = 0
\n" ); document.write( "x = 60
\n" ); document.write( "This is the height of the tree = 60 metres
\n" ); document.write( "Hope htis helps:-) \n" ); document.write( "
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