Y= -1/3x is the equation of tge perpendicular line
Answer:
<h2>7/8 as a fraction</h2>
Step-by-step explanation:
12.15 km /h
Step-by-step explanation:
Step 1 :
Given
Distance between Airy Town to Brightvale = 9 km
Speed of Ricky = x km/h
Step 2:
Speed taken by Sam = x + y km/h
Time taken by Sam = 40 min = 40/60 hrs = 2/3 hrs
so we have (x+y) 2/3 = 9
Step 3:
Speed taken by Timothy = x - y km / h
Time taken by Timothy = 50 min = 50/60 = 5/6 hrs
= > (x-y) 5/6 = 9
Step 4 :
Solving the 2 equations
(x+y) 2/3 = 9 and (x-y) 5/6 = 9 we have
(2/3)x + 2/3(y) = 9 = > 2x + 2 y = 27
5/6(x) - 5/6(y) = 9 = > 5 x - 5 y = 54
Multiplying the first equation by 5 and the second by 2 we have ,
10 x + 10 y = 135 and 10 x - 10y = 108
Adding both,
20 x = 243 => x = 12.15.
This gives speed of Ricky as 12.15 km /h
Answer:
160 mph
Step-by-step explanation:
The relationship between time, speed, and distance is ...
time = distance/speed
__
If p represents the plane's speed, then the speed with the wind is p+20 and the time to go 405 miles is ...
405/(p+20)
The speed against the wind is p-20, and the time to go 315 miles is ...
315/(p-20)
These two times are equal, so we have ...
405/(p+20) = 315/(p-20)
405(p-20) = 315(p+20) . . . . . . cross multiply
90p = 6300 +8100 = 14400 . . . . add 8100 -315p
p = 14400/90 = 160
The speed of the plane in still air is 160 mph.
I am confident that the answer is C. 53.7