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:
12
Step-by-step explanation:
6(-1)+(-2)
-6(-2)
12
I might be wrong so please forgive me if I am.
The circumference can be obtained fairly easily by simply substituting the d in c = πd for the colony's given diameter of 12 mm. Performing that calculation using the approximation of π ≈ 3.14, we obtain a circumference of 12 x 3.14 = 37.68 mm.
To find the radius, remember how the diameter and radius of a circle are defined. The radius is a length extending from the center of a circle to a point on its circumference, and a diameter is a line extending from one point on the circle's circumference to an opposite point, passing through the circle's center along the way. The diameter can, in this way, be defined as twice the length of the radius, which means we can find the radius of a circle by taking half of its diameter. In this case, our diameter is 12 mm, so our radius would be 6 mm.
Answer:
sry I just wanted the points I'm in middle school so I don't know this stuff either but can you give free brainlyest I'm soo close to my next rank I'd really appreciate it if you would
