SOLUTION: Two busea A and B leave the same bus depot, A towards the north and B towards the East. After four hours the distance between the two buses is 100 km. Determine the speed of the
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-> SOLUTION: Two busea A and B leave the same bus depot, A towards the north and B towards the East. After four hours the distance between the two buses is 100 km. Determine the speed of the
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Question 1106726: Two busea A and B leave the same bus depot, A towards the north and B towards the East. After four hours the distance between the two buses is 100 km. Determine the speed of the bus A if it travels at a speed of 5 km/hr more than that of bus B. Answer by rothauserc(4718) (Show Source):
You can put this solution on YOUR website! Use Pythagorean Theorem and rate * time = distance
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(4x+20)^2 + (4x)^2 = 100^2
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16x^2 +160x +400 +16x^2 = 10000
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32x^2 +160x -9600 = 0
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x^2 +5x -300 = 0
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(x+20)*(x-15) = 0
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we have two solutions for x, -20 and 15
we reject the negative solution
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x = 15
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A = 15 +5 = 20 km/hr
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