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!
It is a quadratic equation, if it is equal to zero. It is not factor able.
Answer:
Step-by-step explanation:Worked out on paper shown below
Also I recommended a online app called (it has wierd name but it’s helpful for algebra) mathpapa
Also I do math in pen so the last answer is messed up it’s 4c^2d and then the rest of the parentheses.Sorry for that.
Answer:
0.012
Step-by-step explanation:
Simplify the expression:
8(2x - 3) - 6x = 8×2x - 8×3 - 6x = 16x - 24 - 6x = 10x - 24
for x=3
put value of "x" to the expression:
<u>10×3 - 24 = 30 - 24 = 6</u>