Find the vertex of y=x^2+8x+15

Use the normal approximation to the binomial distribution to answer this question. fifteen percent of all students at a large university are absent on mondays. if a random sample of 12 names is called on a monday, what is the probability that four students are absent?

I’m really confused and need your assist me with this question i’ve never been taught

Using the rise/run counting method, the slope of the line is