All categories

2 years ago

Multiply and show all steps please!!

Mathematics

2 answers:

Mazyrski [523]2 years ago

5 0

the answer is 80 take the positive and negative and use the sign change rule

garik1379 [7]2 years ago

4 0

Answer:

Step-by-step explanation:

First, find the square roots.

$\sqrt{-16} =4i$

$\sqrt{-64} =8i$

Remember: i stands for $\sqrt{-1}$

Then use the FOIL method to multiply.

(3+4i)(6-8i)

18-24i+24i-32i²

i²= -1, so :

18+32

I have no idea what the other person did, but its wrong.

You might be interested in

The Discriminant of a quadratic equationis is -6 .What types of solutions does the equation have ?

Ludmilka [50]

I’m pretty sure the answer is C

8 0

3 years ago

Read 2 more answers

Find the complex zeros of the following polynomial tunction and use the complex zeros to factor f

kramer

Answer:

x = 5 or x = 5 + 2 i or x = 5 - 2 i

Step-by-step explanation:

Solve for x:

x^3 - 15 x^2 + 79 x - 145 = 0

Hint: | Factor the left-hand side.

The left hand side factors into a product with two terms:

(x - 5) (x^2 - 10 x + 29) = 0

Hint: | Find the roots of each term in the product separately.

Split into two equations:

x - 5 = 0 or x^2 - 10 x + 29 = 0

Hint: | Look at the first equation: Solve for x.

Add 5 to both sides:

x = 5 or x^2 - 10 x + 29 = 0

Hint: | Look at the second equation: Solve the quadratic equation by completing the square.

Subtract 29 from both sides:

x = 5 or x^2 - 10 x = -29

Hint: | Take one half of the coefficient of x and square it, then add it to both sides.

Add 25 to both sides:

x = 5 or x^2 - 10 x + 25 = -4

Hint: | Factor the left-hand side.

Write the left hand side as a square:

x = 5 or (x - 5)^2 = -4

Hint: | Eliminate the exponent on the left-hand side.

Take the square root of both sides:

x = 5 or x - 5 = 2 i or x - 5 = -2 i

Hint: | Look at the second equation: Solve for x.

Add 5 to both sides:

x = 5 or x = 5 + 2 i or x - 5 = -2 i

Hint: | Look at the third equation: Solve for x.

Add 5 to both sides:

Answer: x = 5 or x = 5 + 2 i or x = 5 - 2 i

7 0

3 years ago

The age at which small breed dogs are fully housebroken follows a Normal distribution with mean ms = 6 months and standard devia

atroni [7]

Answer:

This measure is just 0.17 standard deviations from the mean, so we should not be surprised.

Step-by-step explanation:

Normal probability distribution

When the distribution is normal, we use the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

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 pvalue, we get the probability that the value of the measure is greater than X.

If the z-score is lower than -2, or higher than 2.5, the score of X is considered unusual.

Subtraction of normal variables:

When we subtract normal variables, the mean is the subtraction of the means, while the standard deviation is the square root of the sum of the variances.

Let xS – xL represent the sampling distribution.

Mean s 6, means L 4. So

$\mu = 6 - 4 = 2$

Standard deviation s is 2.5, for L is 1.5. So

$\sigma = \sqrt{2.5^2+1.5^2} = 2.915$

Should we be surprised if the sample mean housebroken age for the small breed dogs is at least 2.5 months more than the sample mean housebroken age for the large breed dogs? Explain your answer.

We have to find the z-score for X = 2.5. So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{2.5 - 2}{2.915}$

$Z = 0.17$

This measure is just 0.17 standard deviations from the mean, so we should not be surprised.

7 0

2 years ago

Solve for x and simplify answer as much as possible

pantera1 [17]

Answer:

$x=-1$

Step-by-step explanation:

$4=6+2x$

Flip the equation:

$2x+6=4$

Subtract 6 from both sides:

$3x+6-6=4-6$

$2x=-2$

Divide both sides by 2:

$2x/2=-2/2$

$x=-1$

3 0

2 years ago

Read 2 more answers

sketch and label the sampling distribution for the sample proportion of games containing a "big bang", according to the Central

Daniel [21]

Answer: D

Step-by-step explanation:

Sketch and label the sampling distribution for the sample proportion of games containing a big bang, according to the Central Limit Theorem, assuming that the grandfather's null hypothesis is true. Also check whether or not the conditions hold for the CLT to apply. Of the 95 games in our sample, 47 contained a big bang.

8 0

2 years ago