document.write( "Question 624781: A car leaves an intersection traveling west. Its position 4 sec later is 18 ft from the intersection. At the same time, another car leaves the same intersection heading north so that its position 4 sec later is 29 ft from the intersection. If the speeds of the cars at that instant of time are 7 ft/sec and 11 ft/sec, respectively, find the rate at which the distance between the two cars is changing. \n" ); document.write( "

Algebra.Com's Answer #393049 by Alan3354(69443) $\"\"$ $\"About$

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A car leaves an intersection traveling west. Its position 4 sec later is 18 ft from the intersection. At the same time, another car leaves the same intersection heading north so that its position 4 sec later is 29 ft from the intersection. If the speeds of the cars at that instant of time are 7 ft/sec and 11 ft/sec, respectively, find the rate at which the distance between the two cars is changing.
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\n" ); document.write( "The distances from the intersection are not relevant if they leave the intersection at the same time. It's a Pythagorean calculation.
\n" ); document.write( " $\"r+=+sqrt%287%5E2+%2B+11%5E2%29\"$
\n" ); document.write( "r =~ 13.04 ft/sec
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\n" ); document.write( "\"instant of time\" is redundant and fails at pedantry. instant is sufficient, as instants always implies time.
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\n" ); document.write( "Also, \"respectively\" serves no purpose.
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\n" ); document.write( "Math tutor, grammar nazi.\r
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