There would be 12 people at the party!
In general, with n+1 people, the number of handshakes is the sum of the first n consecutive numbers: 1+2+3+ ... + n.
Since this sum is n(n+1)/2, we need to solve the equation n(n+1)/2 = 66.
This is the quadratic equation n2+ n -132 = 0. Solving for n, we obtain 11 as the answer and deduce that there were 12 people at the party.
Since 66 is a relatively small number, you can also solve this problem with a hand calculator. Add 1 + 2 = + 3 = +... etc. until the total is 66. The last number that you entered (11) is n.
Hope this helps!
Answer:
9,801
Step-by-step explanation:
99*99=9,801
Answer:
28.75 or 28 3/4
Step-by-step explanation:
This equation is made for Long Division:
115/4
4 cannot go into 1 evenly.
4 can go into 11, 2 times.
4x2=8
11-8=3
4 can go into 35, 8 times.
35-32=3
Add a zero at the end, then divide 4 into 30.
4 goes into 30, 7 times.
30-28=2
Add another zero, then divide again.
4 goes into 20, 5 times.
20-20=0
So, after you hit an even number you can stop dividing and put in your answer.
28.75
The last one is not necessarily true
The polynomial has two terms. The exponent of the first term is two. The exponent of the second term would be 1 because 5xy^1 is equal to 5xy.
