Normal-travel DATA:
distance = 240 km
rate = x km/h
time = d/r
= 240/x hrs
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Bad weather DATA:
distance = 240 km
rate = (x-20) km/h
time = 240/(x-20) hrs
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Bad time - normal time = 2 hrs
240/(x-20) - 240/x = 2
120/(x-20) - 120/x = 1
120x -120(x-20) = x(x-20)
20 = x^2 -20x
x^2 - 20x - 20 = 0
x = [20 +- sqrt(20^2 - 4*1*-20)]/2
x = [20 +- sqrt(480)]/2
x = [20 +- 4sqrt(30)]/2
x = 10 +- 2sqrt(30)
Answer:
domain: -infinity < x <infinity or (-infinity, infinity)
range: -infinity < f(x) < infinity or (-infinity, infinity)
Step-by-step explanation:
Answer:
Area of shaded region = 28 in^2
Step-by-step explanation:
Area of rectangle = 8 x 5 = 40 in^2
Area of triangle = 1/2 x 8 x 3 = 12 in^2
Area of shaded region = 40 in^2 - 12 in^2 = 28 in^2
Answer:
2 3/7 is 2.42 + 3.56 is 5.98
Step-by-step explanation:
Robert earned $209.51 more than David.
Robert: $896.36
David: $686.85
$896.36 - $686.85 = $209.51
