Answer: 60480
Step-by-step explanation:
Given : The number of empty seats in a theater = 9
The number of customers need to find places to sit =6
Since order matters here, so we use permutations
The permutations of n things taking r at a time is given by :-

Then, the number of ways to arrange 6 seat in 9 seats :-

Hence, the number of ways to arrange 6 seat in 9 seats = 60480
Answer:
50
Step-by-step explanation:




Plug 10 in for x.

Its an indirect proof, so 3 steps :-
1) you start with the opposite of wat u need to prove
2) arrive at a contradiction
3) concludeReport · 29/6/2015261
since you wanto prove 'diagonals of a parallelogram bisect each other', you start wid the opposite of above statement, like below :- step1 : Since we want to prove 'diagonals of a parallelogram bisect each other', lets start by assuming the opposite, that the diagonals of parallelogram dont bisect each other.Report · 29/6/2015261
Since, we assumed that the diagonals dont bisect each other,
OC≠OA
OD≠OBReport · 29/6/2015261
Since, OC≠OA, △OAD is not congruent to △OCBReport · 29/6/2015261
∠AOD≅∠BOC as they are vertical angles,
∠OAD≅∠OCB they are alternate interior angles
AD≅BC, by definition of parallelogram
so, by AAS, △OAD is congruent to △OCBReport · 29/6/2015261
But, thats a contradiction as we have previously established that those triangles are congruentReport · 29/6/2015261
step3 :
since we arrived at a contradiction, our assumption is wrong. so, the opposite of our assumption must be correct. so diagonals of parallelogram bisect each other.