I’m confused on the question…please retype it and i’ll be able to answer
Answer:
The mean number of households who own a riding lawn mower is 6.65.
Step-by-step explanation:
For each household, there are only two possible outcomes. Either there is a riding lawn mower, or there is not. The probability of a household having a riding lawn mower is independent of other households. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
Probability of exactly x sucesses on n repeated trials, with p probability.
The expected value of the binomial distribution is:

35% of households own a riding lawn mower.
This means that 
A sample 19 households is studied.
This means that 
What is the mean number of households who own a riding lawn mower

The mean number of households who own a riding lawn mower is 6.65.
5x^2 + 25x = 0
5x(x + 5) = 0
x = 0, -5
The answer is: x = 0 and x = -5.