In the problem below, you are given two lines. One corresponds to male enrollment in college and the other to female enrollment in college. The goal is to use these models to find when male enrollment equals female enrollment.
Problem Suppose the percent of males who enroll in college within 12 months of high school graduation is given by
y = -0.126x + 55.72
and the percent of females who enroll in college within 12 months of high school graduation is given by
y = 0.73x + 39.7,
where x is the number of years after 1960. Find the year these models indicate that the percent of females equaled the percent of males.
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The x values in this problem correspond to years after 1960. Don’t be tempted to round the value to 19 and say the year is 1979. Since it asked in what year, 1960 + 18.71 is 1978.71 so the year they were equal is 1978.