Need help with slopes please

Solve x2 + 2x = 4 for x by completing the square. x equals plus or minus square root of 5 plus 1 x equals plus or minus square r

steposvetlana [31]

Answer:

x equals plus or minus square root of 5 minus 1

Step-by-step explanation:

we have

$x^{2} +2x=4$

Divide by 2 the coefficient of the x-term

$2/2=1$

squared the number

$1^2=1$

Adds both sides

$x^{2} +2x+1=4+1$

$x^{2} +2x+1=5$

Rewrite as perfect squares

$(x+1)^{2}=5$

take the square root both sides

$x+1=(+/-)\sqrt{5}$

$x=(+/-)\sqrt{5}-1$

therefore

x equals plus or minus square root of 5 minus 1

4 0

3 years ago

The aquarium holds 150 liters of water. How many milliliters is this?

klio [65]

I think it would be150,000 ml
hope this helps :D

7 0

3 years ago

Read 2 more answers

4. Which operation should be completed first in the expression below? Use PEMDAS to evaluate. 24 ÷ (12 – 8) x 6 + 3 a. Add b. Su

irinina [24]

Answer:

Option b - Subtract

Step-by-step explanation:

Given : Expression $24\div(12-8)\times 6+3$

To find : Which operation should be completed first in the expression below?

Solution :

P - Parentheses

E - Exponent

D - Divide

M - Multiplication

A - Addition

S - Subtraction

In the first step we solve the bracket in the expression $24\div(12-8)\times 6+3$

So, we do subtraction i.e. 12-8=4

Therefore, option b is correct.

5 0

3 years ago

Is 21 to the square root of 2 rational or irrational

Step2247 [10]

It is equal to 21/2 which is a rational number

3 0

3 years ago

Suppose that the population mean for income is $50,000, while the population standard deviation is 25,000. If we select a random

Fudgin [204]

Answer:

Probability that the sample will have a mean that is greater than $52,000 is 0.0057.

Step-by-step explanation:

We are given that the population mean for income is $50,000, while the population standard deviation is 25,000.

We select a random sample of 1,000 people.

Let $\bar X$ = sample mean

The z-score probability distribution for sample mean is given by;

Z = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\mu$ = population mean = $50,000

$\sigma$ = population standard deviation = $25,000

n = sample of people = 1,000

The Z-score measures how many standard deviations the measure is away from the mean. After finding the Z-score, we look at the z-score table and find the p-value (area) 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.

So, probability that the sample will have a mean that is greater than $52,000 is given by = P( $\bar X$ > $52,000)

P( $\bar X$ > $52,000) = P( $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ > $\frac{52,000-50,000}{\frac{25,000}{\sqrt{1,000} } }$ ) = P(Z > 2.53) = 1 - P(Z $\leq$ 2.53)

= 1 - 0.9943 = 0.0057

Now, in the z table the P(Z $\leq$ x) or P(Z < x) is given. So, the above probability is calculated by looking at the value of x = 2.53 in the z table which has an area of 0.9943.

Therefore, probability that the sample will have a mean that is greater than $52,000 is 0.0057.

5 0

3 years ago