1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Artyom0805 [142]
3 years ago
10

At a party, everyone shook hands with everybody else. There were 66 handshakes. How many people were at the party?

Mathematics
2 answers:
Gnoma [55]3 years ago
3 0

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!

nataly862011 [7]3 years ago
3 0

Answer:

Uhm. You didnt get this from me, But If there was 66 handshakes, and each person shakes another persons hand, all you gotta do is divide it by 2 and you get 66.

Step-by-step explanation:

Im right ik ty ;)

You might be interested in
If a₀ , a₁ , a₂ , a₃ , are all positive , then 4a₀x³ + 3a₁x² + 2a₂x + a₃ = 0 has at least one root in (-1,0) if
artcher [175]
If f(x)=4a_0x^3+3a_1x^2+2a_2x+a_3, then you have

f(-1)=-4a_0+3a_1-2a_2+a_3
f(0)=a_3

By the intermediate value theorem, there will be some number -1 such that f(c)=0 (i.e. f(x) will have a root in (-1,0)) if you can guarantee that f(-1) or f(-1)>f(c)>f(0).

Since the coefficients a_i are all positive, then you know right away that f(0)>0, so you need to have f(-1) in order for there to be such a c.

This means you need to have

-4a_0+3a_1-2a_2+a_33a_1+a_3

which means (A) must be the answer.
7 0
3 years ago
Edward bought 2 Xbox games and 3 Playstation games for $210. Let x represent the Xbox games and y represent the Playstation game
zimovet [89]
2X •3y=210. hoped I helped
3 0
3 years ago
Help with math homework pls!
Svetach [21]

the correct answer is a^6


5 0
3 years ago
When graphing, one always marks FIRST​
Ket [755]

Answer:

The y-intercept on the y-axis

Step-by-step explanation:

The y-intercept is where you start graphing. That's why it's important to find that first.

Hope this helps!!

7 0
2 years ago
Evaluate the expression 3⋅f(−4)−3⋅g(−2)
wel

Answer:

-6g

Step-by-step explanation:

3 0
3 years ago
Other questions:
  • If a b and c d which pair of angles are congruent
    12·1 answer
  • When a colcano erupts the height of the peak id reduced and the upper portion is removed the height of a volcano after it erupte
    9·1 answer
  • Y=a(x-3)^2-1 what is the value of a?
    6·1 answer
  • I need help with 4 and 5 please
    8·1 answer
  • Please help me!!!!!!!!
    15·1 answer
  • Please help me with this very troubling algebra question, Thank you.
    8·1 answer
  • Find the solution of this system of equations.
    5·2 answers
  • Nina's school is 3 miles north of her house and the library is 5 miles west. If Nina walks directly from her school to the libra
    8·1 answer
  • Miranda invited 117 guests to a charity event. Miranda is renting tables that seat 9 guests at each table. If each table costs ​
    12·1 answer
  • Wwiwwiwiwiwieqwertuttuyiueip
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!