Andre surveyed a random sample of 20 students and found that 13 of them were in favor of having school
start one hour later. The school has 250 students. Make
an estimate, based on Andre's survey for the number of
students in the school who are in favor of having school
start one hour later.
O 65 students
O 87 students
163 students
170 students

Step-by-step explanation:

the answer is a.

135 and 80

step-by-step explanation:

let's call the solutions x₁ = (5 - 2√7)/3 and x₂ = (5 + 2√7)/3

then the equation is (x-x₁)(x-x₂) = 0

if you fill that in you get a lot of numbers which you can recognize as ax²+bx+c=0.

step-by-step explanation:

you can see that a=1 (there is just an x²)

b = (-5 -2√7 + 2√7 - 5)/3 = -10/3

c = -2√7)/3 ) * (-5+2√7)/3) = -1/3

so your answer is 3x^2 – 10x – 1 = 0