Step-by-step explanation:
There are 7 books that can go in the first spot.
After a book has been placed in the first spot, there are 6 books left that can go in the second spot.
After that, there are 5 books that can go in the third spot.
So on and so forth.
So the number of ways is:
7×6×5×4×3×2×1 = 7! = 5040
Answer:
(9, 0)
Step-by-step explanation:
We have to solve the system of equations given:
x + 2y = 9
x + 7y = 9
Firstly, lets solve for x in the 1st equation:
x = 9 - 2y
Now substitute this into 2nd equation to solve for y:
x + 7y = 9
(9 - 2y) + 7y = 9
9 -2y + 7y = 9
5y = 0
y = 0
Now replacing y = 0 into first equation, we can solve for x:
x + 2y = 9
x + 2(0) = 9
x + 0 = 9
x = 9
So, the solution is x = 9, y = 0
or
<u>(9, 0)</u>
Answer: The value of the sine of ∠C is 0.28.
Step-by-step explanation:
Let's draw a triangle again (see the picture below).
Remember SOHCAHTOA? It's:
-sin = opposite/hypotenuse
-cos = adjacent/hypotenuse
-tan = opposite/adjacent.
We need to use sin in here.
The sin of C is 
, which in a calculator, gives 
