document.write( "Question 914830: Aeroplane left 30 minutes later than its scheduled time and in order to reach distination 1500 KM away in time,it has to increase its speed by 250 km/h from its usual speed.determine it usual speed \n" ); document.write( "

Algebra.Com's Answer #555317 by lwsshak3(11628) $\"\"$ $\"About$

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Aeroplane left 30 minutes later than its scheduled time and in order to reach distination 1500 KM away in time,it has to increase its speed by 250 km/h from its usual speed.determine it usual speed
\n" ); document.write( "***
\n" ); document.write( "let x=usual speed of plane
\n" ); document.write( "x+250=increased speed of plane
\n" ); document.write( "30 min=1/2 hr
\n" ); document.write( "travel time=distance/speed
\n" ); document.write( "...
\n" ); document.write( " $\"1500%2Fx-1500%2F%28x%2B250%29=1%2F2\"$
\n" ); document.write( "lcd:x(x+250)
\n" ); document.write( "1500(x+250)-1500x=x(x+250)/2
\n" ); document.write( "1500x+375000-1500x=x^2+250x/2
\n" ); document.write( "750000=x^2+250x
\n" ); document.write( "x^2+250x-750000=0
\n" ); document.write( "(x+1000)(x-750)=0
\n" ); document.write( "x=750
\n" ); document.write( "usual speed of plane=750 km/hr \n" ); document.write( "

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