Please help me. i don’t understand this at all

Help me plz i don't even know if the first one is correct

dimulka [17.4K]

Here's what i got:

Answer:

A)

2.2 * 10^7

B)

0.072 = 7% are female

C)

0.10455 * 22,000,000 = C

0.10455 * 22,000,000 = 2,300,100

D)

0.0195 = 2% of the living veterans served in both.

4 0

3 years ago

Select all of the factors of x3 + 5x2 + 2x – 8.

gladu [14]

The factors of this polynomial would be (x + 4)(x + 2)(x - 1).

To find these, you first have to start with long division to find the first factor. If you use x + 4 it would look like this.

$\frac{x^{3} + 5x^{2} + 2x - 8}{x + 4}$ = $x^{2} + x - 2$

Now we are left with only $x^{2} + x - 2$ . We can factor this by looking for numbers that multiply to the last number and add to the middle number. 2 and -2 multiply to -2 and add to 1. Therefore, we'll use those in parenthesis in their place.

(x + 4)(x + 2)(x - 1)

5 0

3 years ago

Read 2 more answers

Use Gaussian elimination to write each system in triangular form

Feliz [49]

Answer:

To see the steps to the diagonal form see the step-by-step explanation. The solution to the system is $x = -\frac{1}{9}$ , $y= -\frac{1}{9}$ , $z= \frac{4}{9}$ and $w = \frac{7}{9}$

Step-by-step explanation:

Gauss elimination method consists in reducing the matrix to a upper triangular one by using three different types of row operations (this is why the method is also called row reduction method). The three elementary row operations are:

Swapping two rows
Multiplying a row by a nonzero number
Adding a multiple of one row to another row

To solve the system using the Gauss elimination method we need to write the augmented matrix of the system. For the given system, this matrix is:

$\left[\begin{array}{cccc|c}1 & 1 & 1 & 1 & 1 \\1 & 1 & 0 & -1 & -1 \\-1 & 1 & 1 & 2 & 2 \\1 & 2 & -1 & 1 & 0\end{array}\right]$

For this matrix we need to perform the following row operations:

$R_2 - 1 R_1 \rightarrow R_2$ (multiply 1 row by 1 and subtract it from 2 row)
$R_3 + 1 R_1 \rightarrow R_3$ (multiply 1 row by 1 and add it to 3 row)
$R_4 - 1 R_1 \rightarrow R_4$ (multiply 1 row by 1 and subtract it from 4 row)

$R_2 \leftrightarrow R_3$ (interchange the 2 and 3 rows)

$R_2 / 2 \rightarrow R_2$ (divide the 2 row by 2)
$R_1 - 1 R_2 \rightarrow R_1$ (multiply 2 row by 1 and subtract it from 1 row)
$R_4 - 1 R_2 \rightarrow R_4$ (multiply 2 row by 1 and subtract it from 4 row)
$R_3 \cdot ( -1) \rightarrow R_3$ (multiply the 3 row by -1)
$R_2 - 1 R_3 \rightarrow R_2$ (multiply 3 row by 1 and subtract it from 2 row)
$R_4 + 3 R_3 \rightarrow R_4$ (multiply 3 row by 3 and add it to 4 row)
$R_4 / 4.5 \rightarrow R_4$ (divide the 4 row by 4.5)

After this step, the system has an upper triangular form

The triangular matrix looks like:

$\left[\begin{array}{cccc|c}1 & 0 & 0 & -0.5 & -0.5 \\0 & 1 & 0 & -0.5 & -0.5\\0 & 0 & 1 & 2 & 2 \\0 & 0 & 0 & 1 & \frac{7}{9}\end{array}\right]$

If you later perform the following operations you can find the solution to the system.

$R_1 + 0.5 R_4 \rightarrow R_1$ (multiply 4 row by 0.5 and add it to 1 row)
$R_2 + 0.5 R_4 \rightarrow R_2$ (multiply 4 row by 0.5 and add it to 2 row)
$R_3 - 2 R_4 \rightarrow R_3$ (multiply 4 row by 2 and subtract it from 3 row)

After this operations, the matrix should look like:

$\left[\begin{array}{cccc|c}1 & 0 & 0 & 0 & -\frac{1}{9} \\0 & 1 & 0 & 0 & -\frac{1}{9}\\0 & 0 & 1 & 0 & \frac{4}{9} \\0 & 0 & 0 & 1 & \frac{7}{9}\end{array}\right]$

Thus, the solution is:

$x = -\frac{1}{9}$ , $y= -\frac{1}{9}$ , $z= \frac{4}{9}$ and $w = \frac{7}{9}$

7 0

3 years ago

Albert bought some fish at a grocery store at $2 per pound for salmon and $4 per pound for catfish. He spent a total of $12 on s

Gemiola [76]

Albert bought 2 pounds of catfish and 2 pounds of salmon

Let c represent the amount of catfish in pounds and s represent the amount of salmon in pounds.

He spent a total of $12 on salmon and catfish and bought a total of 4 pounds. Hence:

c + s = 4 (1)

4c + 2s = 12 (2)

Solving equations 1 and 2 simultaneously gives:

c = 2, s = 2

Albert bought 2 pounds of catfish and 2 pounds of salmon

Find out more on equation at: brainly.com/question/2972832

7 0

2 years ago

Please help me! I'm spending 50 points on this question and my last two questions never even got answered!

Verdich [7]

Answer:

C.

Step-by-step explanation:

Domain is only affected if certain values can make the result something that either doesn't make sense or is an error. In your situation, it wants you to find the domain of f/g, which is a fraction. The only rule we have for fractions regarding domain is that we simply can't divide by zero, to find the domain for any fraction with variables in the denominator, what I do is take the denominator, set it equal to 0, and solve for x.

So, if we're taking f/g, we have:

$\frac{3x^2 + x^4 + 2}{4x - 3}$

4x - 3 makes up our denominator, the bottom part of the fraction. So

4x - 3 = 0

4x = 3

x = 3/4

So the denominator is equal to zero when x is equal to 3/4. This would produce an error in any calculator because you can't divide by zero. The domain here is all real numbers except for 3/4.

(For future problems, the only thing to look out for is if your numerator, the top part of the fraction, factors into something that cancels with the bottom. In that case, it wouldn't affect domain because you aren't actually dividing by anything. For example:

$\frac{x^2 - 4}{x-2}$

If we factor the top, we see that x^2 - 4 = (x - 2)(x + 2). In this case, we have (x - 2) in both the top and bottom of the fraction, so it cancels out, and from there nothing else is restricting our domain. It would be all real numbers in a case like that.)

8 0

3 years ago