Answer:
39430 each
Step-by-step explanation:
Answer:
Step-by-step explanation:
The motorist drove at a distance of 90km at a constant speed for the first 40km, and then 20 km/hr faster for the rest of the journey.
The whole journey took him 1hr.
Let S denotes the average speed (in km/hr) for the first 40 km.
Hence we get the following relation,
40/S + (90 - 40)/(S + 20) = 1
or 50/(S + 20) = 1 - 40/S = (S - 40)/S
or (S + 20)(S - 40) = 50S or S^2 - 70S - 800 = 0 or (S - 80)(S + 10) = 0
or S = 80 (km/hr) [Ans]
[S cannot be negative value]
Answer:
This one (look at the attachment)
Step-by-step explanation:
A. $40 is the set price per month and $.035 is the changing rate per minute. If t represents the minutes you use the phone, then you have to multiple that amount by $.035
Watch closely:
You said that x - 5 > 10
Add 5 to each side: x > 15
Did you follow all of that ?