Here you go hopes this helps
PICTURE1: They are both 45
PICTURE2: 810
Answer:
-189
Step-by-step explanation:
You substitute the x for -7 and put it into a calculator.
Answer:
The volume of the observatory is 497.43 
Step-by-step explanation:
i) The diameter of the floor is 10 feet. The floor is circular and has a radius,
r = 
= 5 feet.
Therefore the area of the circular floor of the observatory
= 
= 3.14159 × 
= 78.54 
ii) The observatory is made up of two parts
a) 3 foot tall cylinder
∴ volume of cylinder = × h
= 78.54 × 3
= 235.62
b) hemisphere = 
× 
= 0.6667 × 78.54 × 5 = 261.81
c) Therefore the total volume of the observatory is = a) + b)
= 235.62 + 261.81 = 497.43
Problema Solution
You have 800 feet of fencing and you want to make two fenced in enclosures by splitting one enclosure in half. What are the largest dimensions of this enclosure that you could build?
Answer provided by our tutors
Make a drawing and denote:
x = half of the length of the enclosure
2x = the length of the enclosure
y = the width of the enclosure
P = 800 ft the perimeter
The perimeter of the two enclosures can be expressed P = 4x + 2y thus
4x + 3y = 800
Solving for y:
........
click here to see all the equation solution steps
........
y = 800/3 - 4x/3
The area of the two enclosure is A = 2xy.
Substituting y = 800/3 - 4x/3 in A = 2xy we get
A = 2x(800/3 - 4x/3)
A =1600x/3 - 8x^2/3
We need to find the x for which the parabolic function A = (- 8/3)x^2 + (1600/3)x has maximum:
x max = -b/2a, a = (-8/3), b = 1600/3
x max = (-1600/3)/(2*(-8/3))
x max = 100 ft
y = 800/3 - 4*100/3
y = 133.33 ft
2x = 2*100
2x = 200 ft
