Answer:
C
Step-by-step explanation:
From any point (x, y) on the parabola the focus and directrix are equidistant.
Using the distance formula
= | y - 5 |
Squaring both sides
(x - 4)² + (y - 1)² = (y - 5)² ← distribute the factors in y
(x - 4)² + y² - 2y + 1 = y² - 10y + 25 ( subtract y² - 10y + 25 from both sides )
(x - 4)² + 8y - 24 = 0 ( subtract (x - 4)² from both sides )
8y - 24 = - (x - 4)² ← add 24 to both sides )
8y = - (x - 4)² + 24 ( divide both sides by 8 )
y = - (x - 4)² + 3
Hence
f(x) = - (x - 4)² + 3 → C
Answer:
a. Expected frequency of losses per semester = 0*0.08 + 5*0.16 + 10*0.28 + 15*0.32 + 20*0.14 + 25*0.02
Expected frequency of losses per semester = 11.7 losses per semester
b. Variance = (0-11.7)²*0.08 + (5-11.7)²*016 + (10-11.7)²*0.28 + (15-11.7)²*0.32 + (20-11.7)²*0.14 + (15-11.7)²*0.02
Variance = 10.9512 + 7.1824 + 0.8092 + 3.7848 + 9.6446 + 3.5378
Variance = 35.61
c. As losses equal $60, expected losses per semester = 11.7*$60 = $702
d. Expected losses of all textbooks per semester = 250*11.7*$60 = $175,500
Answer:
9e^5f^6
Step-by-step explanation:
Answer:
160
Step-by-step explanation:
22+18=40, and this was 25% of the cars.
So, 40(4)=160 cars were sold that week.