In the table, what percentage of students earned a grade of 70 or above on the exam? Score
Count
[40-50)
1
[50-60)
2
[60-70)
4
[70-80)
5
[80-90)
2
[90-100)
1

no solution

step-by-step explanation:

there is not enough information in the problem to solve.

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