The rule used to create the arithmetic sequence -2, -4, -6, -8,.. is an = -2 - 2(n-1)
The arithmetic sequence is
-2, -4, -6, -8,...
The initial term = -2
The common difference = The second term - The first term
= -4 - (-2)
= -4 + 2
= -2
The nth term of the arithmetic sequence is
an = a+ (n-1) d
Where a is the initial term
an is the nth term
d is the common difference
Substitute the values in the equation
an = -2 + (n-1)(-2)
Rearrange the terms
an = -2 -2(n-1)
Hence, the rule used to create the arithmetic sequence -2, -4, -6, -8,.. is an = -2 - 2(n-1)
Learn more about arithmetic sequence here
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Answer:
1.) 9
2.) 20
Step-by-step explanation:
1.) 39 is incorrect because they didn't follow the PEMDAS rule.
They subtracted 2 from 15 which is 13, and then they multiplied 13 by 3.
<u>The correct way is to multiply 2 times 3 which is 6, and then subtract 6 from 15 which is 9.</u>
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2.) 12 is incorrect because they didn't use PEMDAS.
They added 8 to 16 which is 24, and then divided 24 by 2.
<u>The correct way is to divide 8 by 2 which is 4, and then add for to 16 which 20.</u>
The volume of a sphere refers to the number of cubic units that will exactly fill a sphere. The volume of a sphere can be found or calculate by using the formula V=4/3πr^3, where r represents the radius of the figure.
In this exercise is given that a sphere has a radius of 4 centimeters and it is asked to find its volume and use 3.14 as the value of π or pi. The first step would be substitute the values into the previous mention formula.
V=4/3πr^3
V=4/3(3.14)(4 cm)^3
V=4/3)(3.14)(64 cm^3)
V=267.9 cm^3
The volume of the sphere is 267.9 cubic centimeters.