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Page 89 It is interesting to see how accurately (or inaccurately) the quadratic approximating equation predicts record times 21c. outside its specified domain. In August 2005, Kenenisa Bekele of Ethiopia ran a record time of 26 minutes 17.54 seconds. (This was still the record in 2008.) In what year does the equation predict this time would be achieved? How many years off the actual date is the prediction? QTCI B 1' 05:2? L Av [3' @Source SIE\":::: Page 90 You are given an equation 0 fthe form y = ax2 + bx + c. (a) Use a graphing utility to graph the equation and to estimate 27. the x-intercepts. (Use a zoomin process to obtain the estimates; keep zooming in until the first three decimal places 0 f the estimate remain the same as you progress to the next step.) (b) Determine the exact values 0 f the intercepts by using the quadratic formula. Then use a calculator to evaluate the expressions that you obtain. Round off the results to four decimal places. [Check to see that your results are consistent with the estimates in part (a).] y= 2x2 + 2J26x +13 u u . u u A .i. V. 1 "II "II lIll llll |||li|i (ETC! B I use? I; Avv Mme Page 89 The chart that follows shows the world records for the men's 10,000 meter run in the years 1972 and 1998. 21a. Time {minutes Year and semnds} Run ner [WE 2?:38.4 Lasso Vircn (Finlandl 1998 26:22.75 Hailc Gebrselusslc [Elhioplal For the years between 1972 and 1998, the world record can be approximated by the equation 1/ = O.09?81t2 + 385.83361 378.850.4046 (1972