Which year is the best prediction for when 1206 people will attend graduate school?
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Answer:
D year 15
Step-by-step explanation:
Given:
y= 8x^2-40x+6
year is the best prediction for when 1206
Finding value of x for y=1206
8x^2-40x+6= 1206
8x^2-40x+6-1206=0
8x^2-40x-1200=0
Solving the above by quadratic formula:
x= [tex]\frac{-b\sqrt{b^{2}-4ac } }{2a}[/tex]
= [tex]\frac{40\sqrt{40^{2}-4(8)(-1200) } }{2(8)}[/tex]
x= 15 and x= -10
As year can not be negative, hence correct answer is
D: year 15!