MATHEMATICS HIGH SCHOOL

The first square number is 1, and the sum of the first 20 square numbers is 2870. Work out the sum of the first 21 square numbers.

Answers

Answer 1
Answer:

If the sum of the first 20 square numbers is 2870  then sum of the first 21 square numbers is 3311.

What is Sequence?

Sequence is an enumerated collection of objects in which repetitions are allowed and order matters.

The first square number is 1, and the sum of the first 20 square numbers is 2870.

We need to find the  sum of the first 21 square numbers.

for first 20 numbers  the answer is

n(n+1)(2n+1)/6

20*21*41/6 = 2870

Now we have to find the sum of first 21 square numbers.

21²=441

Now add it with 2870

2870+441=3311

Hence,  the sum of the first 21 square numbers is 3311.

To learn more on Sequence click:

brainly.com/question/21961097

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Answer 2
Answer: The 21st square number is 21^2 = 441
2870 + 441 = 3311

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The expression (x8 - 48) can be factored as (x2 - 42)2 (x2 + 42)2. a. True b. False
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A case of Mountain Dew (24cans) costs $7.68. What is the unit price?

Answers

Here are the unit rates involved:

$7.68 / 1 case  =  $7.68 per case

$7.68 / 24 cans  =  $0.32 per can

1 case / $7.68  =  0.13 case per $

24 cans / $7.68  =  3.125 cans per $

And of course ...

24 cans / 1 case  =  24 cans per case

1 case / 24 cans  =  0.041666... case per can

Which statements accurately describe the function f(x) = 3radical18^x? Check all that apply.The domain is all real numbers.
The range is y > 3.
The initial value is 3.
The initial value is 9.
The simplified base is .
The simplified base is 3.

Answers

The right answer for the question that is being asked and shown above is that: "The simplified base is 3; The initial value is 9; The range is y > 3." The statements that accurately describe the function f(x) = 3radical18^x is that The simplified base is 3; The initial value is 9; The range is y > 3."

Answer:

The answers are A, C, F

Step-by-step explanation:

Took the quiz and saw the answers, your welcome! ;)

Factor the polynomial.
7x^2 + 68xy - 20y^2

Answers

we notice that it must be a product of 2 different thingummies
so we have
(  x+/-  y)(  x+-/  y)
we need to determine the spaces ad signs
we know that the signs are different since the end result is negative
so fidn the first one
7
factor
7=1 times 7
so we have
(1x+/-    y)(7x+/-    y)
factor end
-20=-1 and 20 or -2 and 10 or -4 and 5
we want the middle term to be positive so the bigger term must be positive

try the ones closest first
(x-4y)(7x+5y)
multiply out the middles and outers
5xy-28xy is not 68xy
try -2 and 10
(x+10y)(7x-2y)
multily middles and outers
-2xy and 70xy=68xy
correct

answer is (x+10y)(7x-2y)

What can multiply to give you 80 but add up to give you 11

Answers


There are no real numbers that can do that job.

There's a pair of complex numbers that can do it.
They are

         5.5 + i4.97
and
         5.5 - i4.97 .

     ' i ' = the imaginary unit = √(-1)

Lots of equations that equal 420? Anybody know some? 

Answers

If we do it algebraically, we get

x + y = 420

This is the simplest equation. You see now this is a linear pair in two variables. Thus, there will be infinitely many solutions.

E.g - 419 + 1 = 420

42 * 10 = 420
21 * 20 = 420

etc,....
42 times 10 
210 times 2
210 + 210
70 times 6
60 tmes 7
140 times 3

 
and etc

True or false: The midpoint of a given line segment must lie on the given line segment?

Answers

Answer:
True

Explanation:
A midpoint of a line is defined as half the distance between these two points.
Therefore, to get this midpoint, we should first connect the endpoints of the line and then get the half the distance

This means that the midpoint must lie on the given line segment

Hope this helps :)
True. The midpoint of a given line segment must lie on the given line segment because it is the half way point of the line. 
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