solve each of the following systems, if possible. indicate whether the system has a unique solution, infinitely many solutions, or no solution.

a. 2x + 10y = 9
3x + 15y = 13

b. 2x + 8y = 5
3x + 12y = 7.5

c. y = 3-x

d. 5x -8y = -1
-5/2 x + 4y = 1/2​

Answer:

Step-by-step explanation:

Answer:

Step-by-step explanation:

-3(2x-7) + 2y + 2 (x+y)

-6x+42 + 2y + 2x + 2y

Take the same coefficents and subtract or add

-6x + 2x= -4x

2y + 2y= 4y

Answer:

B. cos B = 9/41

Step-by-step explanation:

I calculated it logically

Answer:

b

Step-by-step explanation:

cos B = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{BC}{AB}[/tex] = [tex]\frac{9}{41}[/tex] → b

Answer:

you cant send pictures unless created on a graphing website but ill try to help. you first have to simplify y, and if you could comment a clearer equation that would be nice because your equation is confusing(cant tell if its all together

Answer:

3.5

Step-by-step explanation:

Given points are ,

Firstly find the slope of the line passing through these two points . Therefore ,

=> m = y₁ - y₂ / x₁ - x ₂

=> m = ( 3 - 1)/(-2-5)

=> m = -2/7

=> m' = -1/m

=> m' = -1 ÷ -2/7

=> m' = -1 × -7/2

=> m' = 7/2 = 3.5

Answer:

34°

Step-by-step explanation:

90-56=34°

__________

Answer:

1. 0.7421 = 74.21% probability the elevator is overloaded.

2. D.​No, there is a good chance that 10 randomly selected people will exceed the elevator capacity.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

Assume that weights of males are normally distributed with a mean of 166 lb and a standard deviation of 29 lb​.

This means that [tex]\mu = 166, \sigma = 29[/tex]

Sample of 10.

This means that [tex]n = 10, s = \frac{29}{\sqrt{10}}[/tex]

1.The probability the elevator is overloaded is?

Probability that the sample mean is above 160 pounds, which is 1 subtracted by the p-value of Z when X = 160. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

By the Central Limit Theorem

[tex]Z = \frac{X - \mu}{s}[/tex]

[tex]Z = \frac{160 - 166}{\frac{29}{\sqrt{10}}}[/tex]

[tex]Z = -0.65[/tex]

[tex]Z = -0.65[/tex] has a p-value of 0.2579.

1 - 0.2579 = 0.7421

0.7421 = 74.21% probability the elevator is overloaded.

2. Does this elevator appear to be​ safe?

High probability of the elevator being overloaded, so not safe. Correct answer is given by option D.

Answer:

134

Step-by-step explanation:

Answer:

[tex] \frac{3.5}{100} \times 420000 = 14700commission \\ total \: earnings = 50000 + 14700 \\ = 64700[/tex]

Answer:

[tex]\displaystyle x=\left\{0, \frac{2\pi}{3}, \frac{4\pi}{3}\right\}[/tex]

Step-by-step explanation:

We want to solve the equation:

[tex]-2\cos^2(x)=-\cos(x)-1[/tex]

Over the interval [0, 2π).

First, notice that this is in quadratic form. So, to make things simpler, we can let u = cos(x). Substitute:

[tex]-2u^2=-u-1[/tex]

Rearrange:

[tex]2u^2-u-1=0[/tex]

Factor:

[tex](2u+1)(u-1)=0[/tex]

Zero Product Property:

[tex]2u+1=0\text{ or } u-1=0[/tex]

Solve for each case:

[tex]\displaystyle u=-\frac{1}{2}\text{ or } u=1[/tex]

Back-substitute:

[tex]\displaystyle \cos(x)=-\frac{1}{2}\text{ or } \cos(x)=1[/tex]

Using the unit circle:

[tex]\displaystyle x=\left\{0, \frac{2\pi}{3}, \frac{4\pi}{3}\right\}[/tex]

Answer:

Hi, there your answer will 12

2+7+3=12

Have a nice day

Step-by-step explanation:

Answer:

Step-by-step explanation:

I added it up XD Thanks for the points.

Answer:

33

Step-by-step explanation:

2x-7 = 73

2x = 73-7

2x = 66

x = 66÷2

x = 33

Therefore, the value of x is 33

Given:

The term is 7a.

To find:

The coefficient of "a" in the given term "7a"​.

Solution:

In the product of a number and a variable, the number is called the coefficient of that variable.

In the expression "7a", the number is "7" and the variable is "a". It means the number 7 is the coefficient of "a".

Therefore, the coefficient of "a" in the given term "7a" is 7​.

Answer: 625 steps per hour

Step-by-step explanation:

10,000/16=625

Answer:

A

Step-by-step explanation:

this is true due to the ratio of a 30-60-90 triangle, which is 1-2-sqrt(3). The 12 corresponds to the sqrt(3), which means that the 1 corresponds to 4sqrt3 and the 2 to 8sqrt3.

:)

Answer:

54,000 teenagers

Step-by-step explanation:

72/100* 75,000/1=54,000

Answer:

One repetad linear

Step-by-step explanation:

Answer:

their graphed

Step-by-step explanation:

Answer:

I think it's A

Step-by-step explanation:

but I do not know this clearly

Answer: The Answer is A.

I plugged the numbers into Excel.

Step-by-step explanation:

Answer:

8(y+ 5) =3

Step-by-step explanation:

Answer:

103 degrees

Step-by-step explanation:

The angles in a triangle always add up to 180 degrees

so 62+15=77

180-77=103

hope it helps :)

Answer:

103º

Step-by-step explanation:

All angles of a triangle add up to 180º

This means:

62º + 15º + the third angle = 180º

Then you just solve:

180º - 77º = 103º

Hope this helps :)

Answer:

x = 135

Step-by-step explanation:

m = length of perpendicular line to hypotenuse

81/m = m/144

m² = 81 x 144 = 11664

m =√11664 = 108

Using the Pythagorean theorem:

x² = 81² + 108² = 6561 + 11664 = 18225

x = √18225 = 135

9514 1404 393

Answer:

  x = 135

Step-by-step explanation:

Side x is the geometric mean of the hypotenuse segments it touches.

  x = √(81×(81+144)) = √81×√225 = 9×15

  x = 135

Answer:

[tex]f(x)=-9(2)^(^x^-^1^)[/tex]

Explanation:

First, we find the common ratio by dividing any term by its previous term. We should do this a couple of times to make sure it's consistent. In this case, our common ratio is 2. Our first (or 1th) term of the sequence is -9, so our formula becomes

[tex]f(x)=-9(2)^(^x^-^1^)[/tex].

Answer:

u

Step-by-step explanation:

Answer:

180/360 (2 ×22/7×5cm)

18/36=1/2× 2×22/ 7 ×5cm

1×22/7×5cm

22/7×5cm

110/7

=15.715cm

Answer:

1,814,400

Step-by-step explanation:

the formula would be: nPr / x_1 ! x_2!....

since there are 2 O's and it is a 10-LETTER ARRANGEMENT, the equation would now be:

10P10 / 2!

10P10 would simplify down to 10! so you would have :

10! / 2!

if you simplify this above: you would get 1,814,400