A bus travels at 70km/h for x hours and then at 80km/h for 0.5(x+3) hours. the total distance travelled was 460km. Determine x correct to the nearset minute.
well, distance = speed * time, so
70x + 80*0.5(x+3) = 460
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70x + 80*0.5(x+3) = 460
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