Answer:
Step-by-step explanation:
let th numbers be x and y.
x+y=21
y=21-x
Product P=xy=x(21-x)=21 x-x^2
P'=21-2x
P'=0 gives 21-2x=0,x=21/2
P"=-2
which is less than 0 at x=21/2
so P is greatest at x=21/2
y=21-21/2=21/2
P=21/2 ×21/2=441/4=110.25
Answer:
24 mph for both 60 miles and 40 miles.
Step-by-step explanation:
We need to find how long it takes to get to college and from it.
Speed x time (x) = Distance (60)
30x = 60
x=2
It takes two hours to get to college
20x = 60
x = 3
It takes 3 hours to get back. It's a total of 5 hours, 2 hours at 30mph and 3 at 20. Now we need to find the average
30+30+20+20+20=120
120/5= 24
The average speed for the round trip is 24.
To do the second part, we follow the same process, but replace 60 with 40 for distance.
30x=40
x= 1.33
20x=40
x=2
We can add the total distance and divide by total time to find the average.
The total distance is 80. Time is 3.33
80/3.33=24
The average speed is still 24.
The answer to the equation is N>14
Answer:B:(1,-1)
Hope it helps!
The answer is y = x-4.
<u>Step-by-step explanation</u>:
- The given expression is x-y=4
- Keep y alone on one side and move remaining terms to the other side.
⇒ -y = 4-x
- To have y alone, Multiply the above expression with -ve sign on both sides.
⇒ y = x-4