Help pls! 3, 6, 2, x X= 9 7 4

Please help me! The i is an imaginary number (9+4i)^2

beks73 [17]

Answer: 2500

Explanation: I turned the I into a 1 and it turned into a 41 so I added 9+41 which is 50. Then I multiplied 50 by 50 because of the ^2 which gave me 2500. I’m assuming that you can put whatever number as a replacement for the I. I’m sorry if this answer isn’t right.

4 0

2 years ago

Evaluate the summation of negative 2 n minus 3, from n equals 2 to 10..

Alisiya [41]

$\bf \sum\limits_{n=2}^{10}~-2n-3$

so, let's first change the bounds from 1 to 9, so we'll be dropping the indices by 1, in order to do the variable "n".

however, let's use a variable hmmm say "k", where "k" is the value of "n" beginning at 1, thus k = n - 1.

however, if k = n - 1, then k + 1 = n. So let's use those fellows then,

$\bf \sum\limits_{n=2}^{10}~-2n-3\qquad 
\begin{cases}
k=n-1\\
k+1=n
\end{cases}\implies \sum\limits_{k=1}^{9}~-2\stackrel{n}{(k+1)}-3
\\\\\\
\sum\limits_{k=1}^{9}~-2k-2-3\implies \sum\limits_{k=1}^{9}~-2k-5\implies \sum\limits_{k=1}^{9}~-2k-\sum\limits_{k=1}^{9}~5
\\\\\\
-2\sum\limits_{k=1}^{9}~k-\sum\limits_{k=1}^{9}~5\implies -2\left( \cfrac{9(9+1)}{2} \right)\qquad -\qquad (9\cdot 5)
\\\\\\
-2(45)-45\implies -90-45\implies -135$

5 0

3 years ago

Garret grew 2 2/3 inches each year for the past 3 years. How many inches total has Garret grown in the past 3 years ?

fomenos

Answer:

8 inches,

Step-by-step explanation:

2 2/3 = 8/3.

3 * 8/3

= 8 inches,

7 0

3 years ago

First two two terms of the given number sequence 3n + 1 are...

PtichkaEL [24]

Answer:

the sequence begins as {4, 7, ... }

Step-by-step explanation:

a(n) = 3n + 1

The first term is a(1) = 3(1) + 1 = 4, and

the second term is a(s) = 3(2) + 1 = 7

So the sequence begins as {4, 7, ... }

5 0

2 years ago

A certain number of sixes and nines is added to give a sum of 126; if the number of sixes and nines is interchanged, the new sum

galina1969 [7]

Answer:

Original number of sixes = 6

Original number of nines = 10

Step-by-step explanation:

We are told in the question that:

A certain number of sixes and nines is added to give a sum of 126

Let us represent originally

the number of sixes = a

the number of nines = b

Hence:

6 × a + 9 × b = 126

6a + 9b = 126.....Equation 1

If the number of sixes and nines is interchanged, the new sum is 114.

For this second part, because it is interchanged,

Let us represent

the number of sixes = b

the number of nines = a

6 × b + 9 × a = 114

6b + 9a = 114.......Equation 2

9a + 6b = 114 .......Equation 2

6a + 9b = 126.....Equation 1

9a + 6b = 114 .......Equation 2

We solve using Elimination method

Multiply Equation 1 by the coefficient of a in Equation 2

Multiply Equation 2 by the coefficient of a in Equation 1

6a + 9b = 126.....Equation 1 × 9

9a + 6b = 114 .......Equation 2 × 6

54a + 81b = 1134 ........ Equation 3

54a + 36b = 684.........Equation 4

Subtract Equation 4 from Equation 3

= 45b = 450

divide both sides by b

45b/45 = 450/45

b = 10

Therefore, since the original the number of nines = b,

Original number of nines = 10

Also, to find the original number of sixes = a

We substitute 10 for b in Equation 1

6a + 9b = 126.....Equation 1

6a + 9 × 10 = 126

6a + 90 = 126

6a = 126 - 90

6a = 36

a = 36/6

a = 6

Therefore, the original number of sixes is 6

7 0

3 years ago