The first one is the correct answer
Because the boat travels the distance twice as fast when going 3 three miles/hour faster the original speed must be 3 miles/hour. so the distance upstream would be 21 miles/hour.
Answer:
7 minutes
Step-by-step explanation:
average time = 6 minutes per mile
sum = average * count = 6 minutes / mile * 4 miles = 24 minutes
first + last mile = 5 + 5 = 10 minutes
first + second + third + last mile = sum = 24 minutes
second + third = sum - first - last = 24 - 5 - 5 = 24 - 10 = 14 minutes
average of 2 miles in the middle = sum / count = 14 minutes / 2 = 7 minutes
Answer:
b = ⅓
x = ½, -1/7
Step-by-step explanation:
(b−5)x² − (b−2)x + b = 0
(b - 5)(0.5)² - (b - 2)(0.5) + b = 0
0.25b - 1.25 - 0.5b + 1 + b = 0
0.75b = 0.25
b = ⅓
(⅓−5)x² − (⅓−2)x + ⅓ = 0
(-14/3)x² + (5/3)x + 1/3 = 0
14x² - 5x - 1 = 0
14x² - 7x + 2x - 1 = 0
7x(2x - 1) + (2x - 1) = 0
(7x + 1)(2x - 1) = 0
x = 0.5, -1/7
Answer:
x=-2
Step-by-step explanation:
3x-8x = -5x
8+2= 10
5x = 10
simp: x=-2
