Answer:
First question
Circle A:
Radius:2.5 Diameter: 5 Circumference:15.71
Circle B:
Radius:12 Diameter:24 Circumference:75.4
Circle C:
Radius:32 Diameter:64 Circumference:201.06
Circle D:
Radius:42 Diameter:84 Circumference:263.89
Second one:
without Pi
1:81.68
2:37.7
3:263.89
with pi
1:26π
2:12π
3:84π
sorry, i have to keep looking back at the photo
for the last question i will be solving ok
Solve for c :
x⁴ + cx² + 100 = 0
cx² = -(x⁴ + 100)
c = - (x⁴ + 100)/x²
If x = 0, the right side is undefined and c would have no solution.
You will need 119 cups to sell all of the lemonade.
Step-by-step explanation:
Given,
Diameter of cups = 9 cm
Radius of cup = 
Height of cups = 12 cm
We will find volume of cup.

Putting all the values

Therefore;
Each cup can hold 254.34 cubed centimeter of lemonade.
Number of gallons = 8
1 gallon = 3785 cm³
8 gallons = 3785*8 = 30280 cm³
Let,
x = Number of cups
Volume of lemonade in one cup * Number of cups = Volume of 8 gallons
254.34x=30280
Dividing both sides by 254.34

Rounding off to nearest whole number
x = 119
You will need 119 cups to sell all of the lemonade.
Keywords: volume, division
Learn more about volume at:
#LearnwithBrainly
Let
x--------> the border’s length
y--------> the border’s width
P--------> perimeter of the border
we know that
x=5+y------> equation 1
P=2*[x+y]-----> P=2x+2y
P <=180 ft
(2x+2y) <= 180-------> equation 2
substitute the equation 1 in equation 2
2*[5+y]+2y <= 180
10+2y+2y <= 180
4y <= 180-10
4y <=170
y <=42.5 ft
so
the maximum value of the width is 42.5 ft
for y=42.5 ft
x=42.5+5------> x=47.5 ft
the answer is
the width of the border is less than or equal to 42.5 ft
Let the length be x and the width be w
The perimeter will be:
2x+3w=1500
thus
3w=(1500-2x)
w=(1500-2x)/3
w=500-2/3x
The area will be:
A=x*w
A=x(500-2/3x)
A=500x-(2/3)x²
The above is a quadratic equation; thus finding the axis of symmetry we will evaluate for the value of x that will give us maximum area.
Axis of symmetry:
x=-b/(2a)
from our equation:
a=(-2/3) and b=500
thus
x=-500/[2(-2/3)]
x=375
the length will be 375 m
The width will be 250 m