document.write( "Question 124385: Crickets chirp at 59 degrees F 76 chirps per minute. At 65 degrees they chirp 100 times a minute. Write an equation expressing chirping rate in terms of temperature. Then predict chirping rate at 90 degrees F. \n" ); document.write( "
Algebra.Com's Answer #91226 by ankor@dixie-net.com(22740)\"\" \"About 
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Crickets chirp at 59 degrees F 76 chirps per minute. At 65 degrees they chirp 100 times a minute. Write an equation expressing chirping rate in terms of temperature. Then predict chirping rate at 90 degrees F.
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\n" ); document.write( "Write it as a linear equation, x = temp and y = chirps/min
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\n" ); document.write( "find the slope: x1=59; y1=76; x2=65; y2=100
\n" ); document.write( "m =\"%28100+-+76%29%2F%2865+-+59%29\" = \"24%2F6\" = +4
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\n" ); document.write( "Find the equation using the point/slope formula: y - y1 = m(x - x1)
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\n" ); document.write( "y - 76 = 4(x - 59)
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\n" ); document.write( "y - 76 = 4x - 236
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\n" ); document.write( "y = 4x - 236 + 76
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\n" ); document.write( "y = 4x - 160 is our equation
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\n" ); document.write( "Find y when x = 90 (degrees)
\n" ); document.write( "y = 4(90) - 160
\n" ); document.write( "y = 360 - 160
\n" ); document.write( "y = 200 chirps/min at 90 degrees
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\n" ); document.write( "That would also mean that at 40 degrees all chirping will cease, perhaps that
\n" ); document.write( "is when crickets hibernate or something like that. What do you think? \n" ); document.write( "
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