What is the distance between (9,5) and (-2,2)

Factorize: x^2+8x+10 i just solved it but i don't know if the process is correct

The random variable x is the number of occurrences of an event over an interval of ten minutes. it can be assumed that the probability of an occurrence is the same in any two-time periods of an equal length. it is known that the mean number of occurrences in ten minutes is 5.3. the appropriate probability distribution for the random variable

2,10,-50 next two numbers geometric sequence