"n choose k" gives you the number of possible unique combinations...
n!/(k!(n-k)!)
n=number of elements to choose from and k=the number of elements that you choose...in this case:
7!/[2!(7-2)!]
7!/[2!5!]
21
There are 21 possible different two question combinations that she can pick.
Answer:
Yes, the dimensions will be 2x2
Step-by-step explanation:
When multiplying matrices you have AxB by CxD. You can only multiply matrices if the inner number is the same.
Ex. 2x3 by 3x2 or QxD by DxW
The dimensions of the result will depend on the outer numbers.
Ex. 2x3 by 3x2 has a 2x2 result or QxD by DxW has a QxW result
You can get 20 quarters for a five dollar bill. Just divide 5.00 by 0.25 and you get 20. To check, you can multiply 20 by 0.25 and you will get 5.00 or 5.
Solve for
:

Now if
, we have
and

On the other hand, if
, then
and

9514 1404 393
Answer:
yes
Step-by-step explanation:
The figure can be shown to be a parallelogram by showing the sum of endpoints of the diagonals is the same.
A +C = B +D
(0, 6) +(0, -4) = (0, 2) = (3, 5) +(-3, -3) . . . . diagonals bisect each other
If the diagonals of a quadrilateral bisect each other, it is a parallelogram. A parallelogram with a right angle is a rectangle. So, ABCD is a rectangle.
_____
<em>Additional comment</em>
The midpoint of each diagonal is half the sum of the end point coordinates. That is, the midpoints are (0, 2)/2 = (0, 1). Since calculation of the midpoints requires both sums be divided by 2, we can tell the midpoints are the same if the sums are the same.