document.write( "Question 1123733: Karen and David set out from home at the same time. Karen cycles due north 20km/h and David due east at 15km/h. FInd
\n" ); document.write( "a) how far apart they are in 1 hour
\n" ); document.write( "b)after how many minutes they are 10km apart
\n" ); document.write( "c) the bearing of Karen from David at any time
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Algebra.Com's Answer #740200 by ankor@dixie-net.com(22740)\"\" \"About 
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Karen and David set out from home at the same time.
\n" ); document.write( " Karen cycles due north 20km/h and David due east at 15km/h.
\n" ); document.write( "FInd
\n" ); document.write( "a) how far apart they are in 1 hour
\n" ); document.write( "their routes form a right triangle, the hypotenuse is the dist between them
\n" ); document.write( "h = \"sqrt%2820%5E2%2B15%5E2%29\"
\n" ); document.write( "h = 25 km after 1 hr
\n" ); document.write( ":
\n" ); document.write( "b)after how many minutes they are 10km apart
\n" ); document.write( "Change the speeds to km/min
\n" ); document.write( "20/60 = .33 km/min
\n" ); document.write( "15/60 = .25 km/min
\n" ); document.write( "let the t = time in min for them to be 10km apart
\n" ); document.write( "\"%28.33t%29%5E2+%2B+%28.25t%29%5E2+=+10%5E2\"
\n" ); document.write( "\".1111t%5E2+%2B+.0625t%5E2+=+100\"
\n" ); document.write( "\".1736t%5E2+=+100\"
\n" ); document.write( "\"t%5E2+=+100%2F.1736\"
\n" ); document.write( "t^2 = 576
\n" ); document.write( "t = \"sqrt%28576%29\"
\n" ); document.write( "t = 24 min, they are 10 mi apart
\n" ); document.write( ":
\n" ); document.write( "c) the bearing of Karen from David at any time
\n" ); document.write( "Find the angle (David's position) using the tangent tan(A) = \"20%2F15\" = 53 degrees
\n" ); document.write( "In relation to true north, 90-53 = 37 degrees,
\n" ); document.write( "the Bearing then 360 - 37 = 323 degrees is Karen from David
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