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:The answer is 12
Step-by-step explanation:
I cheated
Answer:The measure of angle x is 65°.
Step-by-step explanation: Determine the measure of angle x. Step 1: Add together the known angles. Step 2: Subtract the sum from 180°. The measure of angle x is 65°.
Twenty four multiplied by seven is one hundred sixty eight
Y=7-2×(-5/2)
Y=7+5
Y=12
The answer is C