All categories

1 year ago

What is the value of x in the equation 8x – 2y = 48, when y = 4?

Mathematics

1 answer:

luda_lava [24]1 year ago

8 0

Answer:

Step-by-step explanation:

8x-2y=48, replace y with 4, 8x-2(4)=48, multiply, 8x-8=48, add 8 to both sides to remove the -8, 8x=56 and finally divide by 8 to remove 8 from x, x=7.

You might be interested in

It costs 20 cents to receive a photo and 30 cents to send a photo from a cellphone. C is the cost of one photo (either sent or r

ddd [48]

Answer:

(a) PC(C)= $\left \{ {{0.6 \ \ \ \ x=20} \atop 0.4 \ \ \ \ {x=30}} \right. \\\ 0 \ \ \ \ \ \ \ else$

(b) E[C] = 24 cents

Step-by-step explanation:

Given:

Cost to receive a photo = 20 cents

Cost to send a photo = 30 cents

Probability of receiving a photo = 0.6

Probability of sending a photo = 0.4

We need to find

(a) PC(c)

(b) E[C]

Solution:

(a)

PC(C)= $\left \{ {{0.6 \ \ \ \ c=20} \atop 0.4 \ \ \ \ {c=30}} \right. \\\ 0 \ \ \ \ \ \ \ else$

(b)

Expected value can be calculated by multiplying probability with cost.

E[C] = Probability × cost

E[C] = $0.6\times20 +0.4 \times 30 = 12 + 12 = 24\ cents$

3 0

1 year ago

Cynthia rounds a number, x,to one decimal place. the result is 6.3.

gladu [14]

The answer is: $6.25\leq6.3$

The explanation is shown below:

1. Cynthia rounds the number, which is identified as $x$ , to one decimal place and the result is 6.3.

2. Based on this, we know that $x$ could have been between 6.25 and 6.35. Therefore, the error interval for $x$ is given by:

$6.25\leq6.3$

Where $\leq$ indicates that the value 6.25 is included and indicates that the value 6.35 is not included (Because if $x$ had been exactly 6.35, Cynthia would round up to 6.4).

7 0

1 year ago

The amount of time a passenger waits at an airport check-in counter is random variable with mean 10 minutes and standard deviati

Stolb23 [73]

Answer:

(a) less than 10 minutes

= 0.5

(b) between 5 and 10 minutes

= 0.5

Step-by-step explanation:

We solve the above question using z score formula. We given a random number of samples, z score formula :

z-score is z = (x-μ)/ Standard error where

x is the raw score

μ is the population mean

Standard error : σ/√n

σ is the population standard deviation

n = number of samples

(a) less than 10 minutes

x = 10 μ = 10, σ = 2 n = 50

z = 10 - 10/2/√50

z = 0 / 0.2828427125

z = 0

Using the z table to find the probability

P(z ≤ 0) = P(z < 0) = P(x = 10)

= 0.5

Therefore, the probability that the average waiting time waiting in line for this sample is less than 10 minutes = 0.5

(b) between 5 and 10 minutes

i) For 5 minutes

x = 5 μ = 10, σ = 2 n = 50

z = 5 - 10/2/√50

z = -5 / 0.2828427125

= -17.67767

P-value from Z-Table:

P(x<5) = 0

Using the z table to find the probability

P(z ≤ 0) = P(z = -17.67767) = P(x = 5)

= 0

ii) For 10 minutes

x = 10 μ = 10, σ = 2 n = 50

z = 10 - 10/2/√50

z = 0 / 0.2828427125

z = 0

Using the z table to find the probability

P(z ≤ 0) = P(z < 0) = P(x = 10)

= 0.5

Hence, the probability that the average waiting time waiting in line for this sample is between 5 and 10 minutes is

P(x = 10) - P(x = 5)

= 0.5 - 0

= 0.5

3 0

1 year ago

Which of the following is the best definition of the domain

GalinKa [24]

Answer:

Step-by-step explanation:

8 0

1 year ago

Which expression has the same GCF as 15x2 - 21x?

Mice21 [21]

Answer:

$15x^2 +21 x$

Step-by-step explanation:

We have the following expression:

$15x^2 -21 x$

We can find the GCF with the following steps.

1. Find the GCF for the numerical part 15 and -21

The factors for 15 are : 1,3,5,15

The factors for -21 are -21,-7,-3,-1,1,3,7,21

And the common factors are 1,3

The GCF for the numerical part is 3*1 = 3

2. Find the GCF for the variable

The factors of x^2 are : x*x

The factors of x are: x

The common factors are x for this case, so then the GCF for the variable part is x

3. Multiply the two results from steps 1 and 2

GCf= 3*x = 3x

If we consider the new expression:

$15x^2 +21x$

We can find the GCF with the following steps.

1. Find the GCF for the numerical part 15 and -21

The factors for 15 are : 1,3,5,15

The factors for -21 are 1,3,7,21

And the common factors are 1,3

The GCF for the numerical part is 3*1 = 3

2. Find the GCF for the variable

The factors of x^2 are : x*x

The factors of x are: x

The common factors are x for this case, so then the GCF for the variable part is x

3. Multiply the two results from steps 1 and 2

GCf= 3*x = 3x

And as we can see both GCF are equal. So then we satisfy the condition required.

5 0

1 year ago

Read 2 more answers