Answer:
Step-by-step explanation:
Let f(x) = x². Then
y = -f(x) -5
The negative sign in front of f(x) means the graph is reflected across the x-axis. The addition of -5 means the graph is shifted down 5 units.
the 1st selection is an appropriate description.
Answer:
48.50 dollars.
Step-by-step explanation:
The collector has a total of 224 coins but 74 of them are 25 cents coins. So, in order to find the number of 20-cent coins we're going to subtract the number of 25-cent coins from the total.
Number of 20-cent coins = 224 - 74 = 150.
Thus, the collector has 150 20-cent coins and 74 25-cent coins for a total of 224 coins.
Now, to know the total value of the collection we need to multiply the value of the coins by the number of coins there are of this value (we are going to do it with the 20-cent and the 25-cent coins) and then sum up our results.
Total value = 74(25) + 150 (20) = 1850 + 3000 = 4850 cents.
So the total value is 4850 cents, we know that each dollar has 100 cents so, to express this number in dollars we are going to divide it by 100 and thus we have that the total value of the collection is 48.50 dollars.
Given:
x, y and z are integers.
To prove:
If 
is even, then at least one of x, y or z is even.
Solution:
We know that,
Product of two odd integers is always odd. ...(i)
Difference of two odd integers is always even. ...(ii)
Sum of an even integer and an odd integer is odd. ...(iii)
Let as assume x, y and z all are odd, then is even.
is always odd. [Using (i)]
is always odd. [Using (i)]
is always even. [Using (ii)]
is always odd. [Using (iii)]
is always odd.
So, out assumption is incorrect.
Thus, at least one of x, y or z is even.
Hence proved.
