Answer:
Step-by-step explanation:
Givens
pi = 3.14
d = 10 cm
h = 2*d
Formula
- The top of the cylinder is a solid circle. So the area of the circle is pi r^2
- There is both a top and bottom to the circle so the fomula is 2*pi*r^2
- The surrounding area of the cylinder is the circumference of the circle times the height. The circumference of the circle is 2*pi*r.
- Then you just multiply by the height.
- formula = 2*pi * r * h
The combined formula is given below.
SA = 2*pi*r^2 + 2*pi*r * h
Conversions
d = 10 cm
h = 2*10
h = 20 cm
r = d/2
r = 10 / 2
r = 5cm
Solution
SA = 2*pi*r^2 + 2*pi*r * h
SA = 2*3.14*5^2 + 2*3.14*5*20
SA = 157 + 628
SA = 785 cm^2
Answer: The surface area is 785 cm^2
Answer:
B.24
Step-by-step explanation:
we know,
exterior angle = 360°/n(where 'n' is number of sides)
then,
15° = 360°/n
n = 360°/15°
n = 24
Answer:
1) either 5 or 6 students in the group
2) 6 rooms are booked
Step-by-step explanation:
1) x students
3x + 8 = apples
5 (x-1) + y (the one get less than 5 apples)
3x + 8 = 5 (x - 1) + y
3x + 8 = 5x - 5 + y
2x + y = 13
X 1 2 3 4 5 6
Y 11 9 7 5 3 1
because y < 5 so x = 5 or x = 6
2) x rooms are booked
4x + 20 total students
8 (x-1) + y (the students in room not full))
4x + 20 = 8 (x-1) + y
4x + 20 = 8x - 8 + y
4x + y = 28
X 1 2 3 4 5 6
Y 24 20 16 12 8 4
y < 8 answer is 6 rooms
Pa18 has the right answer
Answer:
the correct answer is x = 3x - 5
