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:
Step-by-step explanation:
bruh
Answer:
c i belive
Step-by-step explanation:
bec why not dude it seems to be self explanatory through the explanation
.
Answer: Yes they can
Step-by-step explanation:
Use Pythagoras rule c²=b²+a²
b²=209
c²=15²=225
a²=4²=16
209+16=225
Answer:
x = 20√2 and y = 20√3.
or x = 28.28 and y = 34.64 to the nearest hundredths.
Step-by-step explanation:
Take the 2 'inside' triangles. They are similar.
So we have x / (60-40) = 40 / x
x/ 20 = 40 /x
x^2 = 800
x = √800
x = 20√2
y = √(800 + 20^2)
= √(1200)
= 20√3.
