What is 5x - 20 + 2x -7

Drina wrote the system of linear equations below.

zalisa [80]

Answer:

Option c, A square matrix

Step-by-step explanation:

Given system of linear equations are

$3x-2y=-2\hfill(1)$

$7x+3y=26\hfill(2)$

$-x-11y=46\hfill(3)$

Now to find the type of matrix can be formed by using this system

of equations

From the given system of linear equations we can form a matrix

Let A be a matrix

A matrix can be written by

A=co-efficient of x of 1st linear equation co-efficient of y of 1st linear equation constant of 1st terms linear equation

co-efficient of x of 2st linear equation co-efficient of y of 2st linear equation constant of 2st terms linear equation

co-efficient of x of 3st linear equation co-efficient of y of 3st linear equation constant of 3st terms linear equation $3\times 3$

which is a $3\times 3$ matrix.

Therefore A can be written as

A= $\left[\begin{array}{lll}3&-2&-2\\7&3&26\\-1&-11&46\end{array}\right] 3\times 3$

Matrix "A" is a $3\times3$ matrix so that it has 3 rows and 3 columns

A square matrix has equal rows and equal columns

Since matrix "A" has equal rows and columns Therefore it must be a square matrix

Therefore the given system of linear equation forms a square matrix

7 0

3 years ago

Read 2 more answers

A function f is differentiable for all values of x in [0,6], and the graph with equation y=f(x) has a local minimum point at (2,

MrRa [10]

Step-by-step explanation:

The slope of tangent line at a max or a minimum is 0,.

So using point slope formula.

$y - 4 = 0(x - 2)$

$y = 4$

Is the equation of a tangent line. This means we have a horizontal line at y= 4. Horizontal lines have a slope of 0.

4 0

2 years ago

If you want Brainliest! You gotta earn it by obviously helping! I need help ASAP, please!

masha68 [24]

Answer:

$\theta=1.72$ radians

Step-by-step explanation:

Arc length and radius is given. So, we need to know the arc length formula for a circle.

That is:

$s=r\theta$

Where s is the arc length

r is the radius

$\theta$ is the angle (IN RADIANS)

We have:

s = 15.5

r = 9

Now, we substitute and find the angle:

$s=r\theta\\15.5=9\theta\\\theta=\frac{15.5}{9}\\\theta=1.72$

The angle, in radians, in 1.72

5 0

3 years ago

A football field is 160 feet wide and 360 feet in length. What is the distance around the field?

charle [14.2K]

Answer: 160 + 160 = 320

360 + 360 = 720

720 + 320 = 1040

6 0

4 years ago

you want to create a 99 confidence interval with a margin of error of 25 assuming that the population standard deviation is equa

Ahat [919]

Answer:

The minimum sample size is 239.

Step-by-step explanation:

We have that to find our $\alpha$ level, that is the subtraction of 1 by the confidence interval divided by 2. So:

$\alpha = \frac{1 - 0.99}{2} = 0.005$

Now, we have to find z in the Z-table as such z has a p-value of $1 - \alpha$ .

That is z with a pvalue of $1 - 0.005 = 0.995$ , so Z = 2.575.

Now, find the margin of error M as such

$M = z\frac{\sigma}{\sqrt{n}}$

In which $\sigma$ is the standard deviation of the population and n is the size of the sample.

Population standard deviation is equal to 1.5

This means that $\sigma = 1.5$

Margin of error of 0.25

This means that $M = 0.25$

What's the minimum size of the sample?

$M = z\frac{\sigma}{\sqrt{n}}$

$0.25 = 2.575\frac{1.5}{\sqrt{n}}$

$0.25\sqrt{n} = 2.575*1.5$

$\sqrt{n} = \frac{2.575*1.5}{0.25}$

$(\sqrt{n})^2 = (\frac{2.575*1.5}{0.25})^2$

$n = 238.7$

Rounding up:

The minimum sample size is 239.

4 0

3 years ago