Answer:
20 sides
We know that if we find the size of an exterior angle for the given regular polygon whose exterior angle is 18∘, we can find the number of sides. Where, n is the number of sides. Therefore, there are 20 sides in the given regular polygon whose exterior angle is 168∘.
Answer:
V = 603.43 cm³
Step-by-step explanation:
V = πr²h
Where r = 4 cm, h = 12 cm
V = 22/7 × 4² × 12
V = 22/7 × 4 × 4 × 12
V = 4224/7
V = 603.43 cm³
Answer:
384 cm²
Step-by-step explanation:
Since it is a square pyramid, the total surface area of the pyramid is the area of its square base plus the area of its 4 triangular faces.
Area of a triangular face
= ½ ×12 ×10
= 60 cm²
Base area of pyramid
= 12 ×12
= 144 cm²
∴ Surface area of pyramid
= 4(60) +144
= 240 +144
= 384 cm²
Answer:
The first number is 20, the second one is 11
Step-by-step explanation:
Let the first number be x and the second number be y
Since it says "9 is the difference between two numbers", the first equation will be x-y=9
It also says that "their sum is 31". That means the second equation will be x+y=31
here are the two equations:
x-y=9
x+y=31
You can solve this any way you like, but I'll show elimination
add the two equations
x-y=9
x+y=31
2x=40
divide by 2
x=20
Substitute 20 as x in one of the equations
20+y=31
subtract 20 from both sides
y=11
That means the two numbers are 20 and 11
Hope this helps!
Answer:
B
Step-by-step explanation:
