Explanation:
a)
b) First, we have that
On the other hand,
Therefore, both expressions are equal. This makes sense, because selecting k elements from a group of n is the same than specify which elements you will not select. In order to specify those elements you need to select the n-k elements that will not be selected. Hence, each time you are selecting k from n, you are also selecting n-k from n, and from that reason both combinatorial numbers are equal.
Answer:
(-6,5)
Step-by-step explanation:
left 2 = x-2
up 3= y+3
For this case, it depends on the context of the problem.
Most of the times the negative numbers in these types of problems mean that we owe money to some person or bank.
For example, if a car costs $ 2000 and I have $ 1500 available, then I must ask for a loan at the bank:
It means that I have to pay $ 500 to the bank.
Answer:
Amount of money you must pay.
Answer:
68
Step-by-step explanation:
Since this is an isosceles triangle the bottom 2 angles are equal. So both bottom angles are 56 degrees. The three angles of a triangle add to 180 degrees.
56+ 56+ x = 180
Combine like terms
112 +x =180
Subtract 112 from each side
112-112+x = 180-112
x =68
Basically just read this and you will understand it better