Can someone explain to me how to do this? im completely confused. and

45

Step-by-step explanation:

Each handshake is between 2 people, so you need to find how many combinations of 2 can be formed from a group of 10 people.

n = 10 and k = 2:

₁₀C₂

10! / (2! (10−2)!)

10! / (2! 8!)

10 × 9 × 8! / (2! 8!)

10 × 9 / 2

45

the answer is:

the answer is:

to solve the problem, we need to remember the quotient of power property, it's defined by the following relation:

if we have a quotienf of powers that have the same base, we need to keep the same base and subtract the exponent of the denominator power to the exponent of the numerator power.

so, we are given the expression:

then, calculating we have:

hence, the answer is:

have a nice day!