Answer:
80 mph
Step-by-step explanation:
<u>First leg of trip</u>
- Speed = 64 mph
- Time = 3 hours
<u>Second leg of trip</u>
- Speed = 92 mph
- Time = 4 hours
To find the average speed:
That would be 20 x 19 x 18 which equals 6840.
After first place is chosen, 19 spots left and so on.
The answer is 6840 ways.
a = 30
a = 16
-a² + 46a -480 = 0
(-a + 30) (a -16) = 0
(-a)(a) + (-a)(-16) + 30(a) + 30(-16) = 0
-a² + 16a + 30a -480 = 0
-a² + 46a - 480 = 0
(-a + 30) = 0 ; (a - 16) = 0
-a = -30 ; a = 16
a = 30
To check:
a = 30
-(30)² + 46(30) - 480 = 0
-900 + 1380 - 480 = 0
480 - 480 = 0
0 = 0
a = 16
-(16)² + 46(16) - 480 = 0
-256 + 736 - 480 = 0
480 - 480 = 0
0 = 0
I'd personally go with A and C, The rest don't make too much sense. Don't count on my answer just yet though.
