Answer:
A
Step-by-step explanation:
Since the triangle is right use Pythagoras' identity to find EF
The square on the hypotenuse is equal to the sum of the squares on the other two sides, that is
EF² + DF² = DE² ← substitute values
EF² + 12² = 18², that is
EF² + 144 = 324 ( subtract 144 from both sides )
EF² = 180 ( take the square root of both sides )
EF = 
→ A
Answer:
-3 + 6 = -3
Step-by-step explanation:
add the terms -3 and 6
exponent law
Answer:
53 1/3 km/h
Step-by-step explanation:
average speed = (total distance)/(total time)
average speed = distance/time
time * average speed = distance
time = distance/(average speed)
250 km at 75 km/h
distance = 250 km
time = (250 km)/(75 km/h) = 3.33333... hours
350 km at 70 km/h
distance = 350 km
time = (350 km)/(70 km/h) = 5 hours
200 km at 30 km/h
distance = 200 km
time = (200 km)/(30 km/h) = 6.6666... hour
total distance = 250 km + 350 km + 200 km = 800 km
total time = 3.33333... hours + 5 hours + 6.66666... hours = 15 hours
average speed = (total distance)/(total time)
average speed = (800 km)/(15 hours)
average speed = 53 1/3 km/h
Circumference=2pir=<span>2∗3.14∗5.1</span><span>=30.028=30.03.</span>
