Answer:
1120 combinations of four teachers include exactly one of either Mrs. Vera or Mr. Jan.
Step-by-step explanation:
The order in which the teachers are chosen is not important, which means that the combinations formula is used to solve this question.
Combinations formula:
is the number of different combinations of x objects from a set of n elements, given by the following formula.
In this question:
1 from a set of 2(Either Mrs. Vera or Mr. Jan).
3 from a set of 18 - 2 = 16. So

1120 combinations of four teachers include exactly one of either Mrs. Vera or Mr. Jan.
Answer:
There's nothing there I believe you forgot to add a link just add or create another question and i'll see what I can do :)
Step-by-step explanation:
Answer:
4
Step-by-step explanation:
Answer:
Step-by-step explanation:

First, on the right-hand side of the equation, let's distribute the
to each term in the parenthesis:

Now, let's move all the terms with an
to the left-hand side, and everything else to the right-hand side of the equation:

Let's combine like terms:

Finally, let's divide each side by
to get
by itself on the left-hand side of the equation:

D. 2x+3 is the right answer