document.write( "Question 251888: Life expectancies at birth for men and women can be modeled by the following functions:
\n" ); document.write( "w(x)= 0.126x+76.74
\n" ); document.write( "M(x)= 0.126x+69.11
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\n" ); document.write( "\n" ); document.write( "W(x) represents the life expectancy of women and M(x) represents the life expectancy of men. The x represents the years since 1975. (x=0 corresponds to the year 1975, x=5 corresponds to 1980, and so on).
\n" ); document.write( "this goes on until 2000
\n" ); document.write( " x is the years since 1975. 1975 0 1985-5 1990-15 1995- 20 2000- 25
\n" ); document.write( "I am not understanding this I also have to figure out on a slope is the life expectantcy of men or women increasing more rapidly. then I have to determine the birth years in a inequality where the men life expectancy are greater than women
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Algebra.Com's Answer #183590 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Since the equation \"W%28x%29=0.126x%2B76.74\" is in slope-intercept form \"y=mx%2Bb\", where 'm' is the slope and 'b' is the y-intercept, this means that the slope is \"m=0.126\".\r
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\n" ); document.write( "\n" ); document.write( "Similarly, for \"M%28x%29=+0.126x%2B69.11\", this equation is also in slope-intercept form \"y=mx%2Bb\" and the slope is \"m=0.126\" as well. So the two slopes are equal.\r
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\n" ); document.write( "\n" ); document.write( "What this means is that the life expectancies are both increasing at the same rate. \r
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\n" ); document.write( "\n" ); document.write( "To find out which years men have a greater life expectancy than women, simply set M(x) (life expectancy of men) greater than W(x) (life expectancy of women) like this\r
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\n" ); document.write( "\n" ); document.write( "\"M%28x%29%3EW%28x%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"0.126x%2B69.11%3E0.126x%2B76.74\" Plug in \"M%28x%29=+0.126x%2B69.11\" and \"W%28x%29=0.126x%2B76.74\"\r
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\n" ); document.write( "\n" ); document.write( "\"1000%280.126x%2B69.11%29%3E1000%280.126x%2B76.74%29\" Multiply both sides by 1000 to clear out the decimals.\r
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\n" ); document.write( "\n" ); document.write( "\"126x%2B69110%3E126x%2B76740\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"126x%3E126x%2B76740-69110\" Subtract \"69110\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"126x-126x%3E76740-69110\" Subtract \"126x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%3E76740-69110\" Combine like terms on the left side.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%3E7630\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"0%3E7630\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "Since this inequality is NEVER true for any value of 'x', this means that the original inequality is also NEVER true.\r
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\n" ); document.write( "\n" ); document.write( "Since there are no solutions to the original inequality, this means that the life expectancy of men will never exceed the life expectancy of women.\r
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\n" ); document.write( "\n" ); document.write( "Note: I would make sure that you copied the problem down correctly (or ask if there are any typos).
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