Answer:
y = (x + 8)² + 6
Step-by-step explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
To obtain this form use the method of completing the square
add/subtract (half the coefficient of the x- term )² to x² + 16x
y = x² + 2(8)x + 64 - 64 + 70
= (x + 8)² + 6 ← in vertex form
Answer:
8 hours
Step-by-step explanation:
12/2= 6
He grades 6 exams per hour
48/6= 8
it would take 8 hours to grade 48 exams
Bonus:
it takes him 10 minutes to grade an exam. That doesnt matter for this question but it's good 2 know