Answer:
ffffffffffffffffffffffffffffffffffdd
Step-by-step explanation:
ddfefe
Answer:
147°
Step-by-step explanation:
106°+139°+126°+141°+112°+129°+x =900°
753°+x = 900°
x = 900°-753°
x= 147° (sum of the interior angles of a heptagon=900°)
Answer: 362,880
Step-by-step explanation: At first glance of the question, it doesn't seem that the order matters, which would make it a question of how many combinations there are. The simple way to look at it is that there are 9 trees and he's planting 8, leaving out 1. Since there are 9 possible trees to leave out, there are 9 possible combinations of which 8 trees to plant.
The formula would be 9!/([9-8]!*8!) = 9
If the question is indeed asking for permutations (order matters), since you are choosing 8 out of 9 the formula would be 9!/(9-8)! = 9!/1! = 9! = 362,880
Answer:
Step-by-step explanation:
- Let the speed of the boat be x
- Speed against the current in the river is x - 2
<u>Time in the river:</u>
<u>Time in the lake:</u>
<u>The difference:</u>
Solve for x to find the speed of the boat
<u>Multiply both sides by x(x - 2) to clear the fraction:</u>
- 6x = 15(x - 2) - x(x - 2)
- 6x = 15x - 30 - x² + 2x
- x² - 11x + 30 = 0
- (x - 5)(x - 6) =0
- x -5 = 0, x - 6 = 0
- x = 5 km/h, x = 6 km/h
