Answer:
diameter of the pizza = 21.88 centimeters
Step-by-step explanation:
Given:
C = d^2 – 2d + 447
where
C = cost of the pizza
d = diameter of the pizza
If the pizza costs $12.00, then what is a reasonable estimate for the diameter of the pizza?
12 = d^2 – 2d + 447
d^2 - 2d = 447 - 12
d^2 - 2d = 435
d^2 - 2d - 435 = 0
Solve the quadratic equation using formula
a = 1
b = -2
c = -435
d = -b +or- √b^2 - 4ac / 2a
= -(-2) +or- √(-2)^2 - (4)(1)(-435) / 2(1)
= 2 +or- √4 - (-1740) / 2
= 2 +or- √4 + 1740 / 2
= 2 +or- √1744 / 2
= 2 +or- 4√109 / 2
= 2/2 +or- 4√109/2
= 1 +or- 2√109
d = 1 + 2√109 or d = 1 - 2√109
= 1 + 2(10.44) or d = 1 - 2(10.44)
= 1 + 20.88 or d = 1 - 20.88
d = 21.88 or -19.88
diameter of the pizza = 21.88 centimeters
Therefore, the estimated diameter of the pizza can not be negative. So, diameter of the pizza = 21.88 cm
You are doing the distributive property.
68.5j+76.54
X/4 - 3
(*make sure to write the division in fraction form as shown for algebraic notation)
(a) (i) In first 4 minutes Mary's speed was 600 / 4 = 150 m / minute
(ii) in last 4 minutes her speed was (1000-600) / 4 = 400/4 = 100 m/min
(b) Marys average speed for the whole journey = 1000/8 = 125 m/min
(c) 200 m
(d) Peter arrived at school after 7 minutes . Mary took 8 minutes. Peter first.
(e) Where they met is given by where the 2 curves intersect. That is at time 6.8 minutes and 880 m from Mary's home
(f) At t= 4 dsitance between then is 600 - 400 = 200 m
52/8 is 6.5 on a calculator, hope this helps