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!
Solving for x you would get X=6
Answer:
answer below
Step-by-step explanation:
ABCDE go through dilation over center (6 , -2) with factor of 1/2 to FGHIJ
AB // FG slope: -2 , √20:√5 = 2: 1
BC // GH // X axis 8:4 = 2:1
CD // HI, slope= 1 , √8:√2 = 2:1
DE // IJ // x axis, 4:2 = 2:1
EA // JF // y axis, 2:1
Answer:
the answer to the question is 39
Answer:
The second one and the fourth one :)
