Posted by Tony on Thursday, July 5, 2012 at 1:48pm.
In one U.S. city, the quadratic function models the median, or average, age, y, at which men were first married x years after 1900. In which year was this average age at a minimum? (Round to the nearest year.) What was the average age at first marriage for that year? (Round to the nearest tenth.)

Math  bobpursley, Thursday, July 5, 2012 at 1:52pm
y= ax^2+bx+ c
using calculus...
dy/dx=2ax+b=0
x=b/2a is either the max, or min.
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