Answer:
28
Step-by-step explanation:
Plug in the corresponding numbers to the corresponding variables. Note that:
m = 7
r = 8
t = 2
mr/t = (7 * 8)/2
(7 * (8/2)) = 7 * 4 = 28
28 is your answer.
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I got 6 units^2. So the answer is the second choice. ab/2 = 3*4/2 = 6.
Answer:
Her speed on the summit was 35 mph.
Step-by-step explanation:
Her speed on the summit was "x" mph while her speed while climbing was "x - 10" mph. The distance she rode uphill was 55 miles and on the summit it was 28 miles. The total time she explored the mountain was 3 hours. Therefore:
time uphill = distance uphill / speed uphill = 55 / (x - 10)
time summit = distance summit / speed summit = 28 / x
total time = time uphill + time summit
3 = [55 / (x - 10)] + 28 / x
3 = [55*x + 28*(x - 10)]/[x*(x - 10)]
3*x*(x - 10) = 55*x + 28*x - 280
3x² - 30*x = 83*x - 280
3x² - 113*x + 280 = 0
x1 = {-(-113) + sqrt[(-113)² - 4*(3)*(280)]}/(2*3) = 35 mph
x2 = {-(-113) - sqrt[(-113)² - 4*(3)*(280)]}/(2*3) = 2.67 mph
Since her speed on the uphill couldn't be negative the speed on the summit can only be 35 mph.
Answer: The second option
Step-by-step explanation: 14mph times 5 equal 70. 5 hours after 6 am is 11 am. 70 divided by 20 is 3.5. 3.5 hours after 6 am is 9:30. Hence 9:30 to 11
3 because the x value has been repeated