What is the factored form of x^2 - 4x - 5?

we are given

x^2-4x-5

we can use formula

x^2-(a+b)x+ab=(x-a)(x-b)

so, we have

a+b=4

ab=-5

now, we can solve for a and b

and we get

a=5, b=-1

now, we can plug it in formula

x^2-4x-5=(x-5)(x+1) Answer

a. the residual plot for model 1 has a random pattern and is a good fit for the data.