Answer:
the expression is: 
and 2730 different ways are possible.
Step-by-step explanation:
In the given question we have to choose a president, vice
president, and secretary.
Permutations are used when order is important so, as in the given question order is required. We would use permutations
The formula used is:
where:
n=total number of objects
r=number of objects selected
In our case: n=15, r=3
Putting values and finding the answer:

So, the expression is: 
and 2730 different ways are possible.
None of them are correct.
You have to isolate the variable by dividing each side by factors that don't contain the variable.
And when you do so you get a closed point starting at positive 8 and an extending ray to positive infinity and a closed point at -15 with a ray extending to negative infinity on the number line so none of them are correct.
Answer:
-8√6
or
-19.59
Step-by-step explanation:
The sides of a square are all the same length.
Area = length x width.
Area = 10 1/4 x 10 1/4 = 105 1/16
Answer:
90°
Step-by-step explanation:
hope this helps.....