All categories

3 years ago

6 (2x - 7) + 4 (2x + 4)

Mathematics

2 answers:

sergey [27]3 years ago

8 0

Answer:

20x - 26

Step-by-step:

6(2x-7) + 4(2x+4)

12x - 42 + 8x + 16

20x - 26

Good Luck

Romashka [77]3 years ago

3 0

Answer: 20x-26

Step-by-step explanation: its hard to explain

You might be interested in

what positive number satisfies the condition that twice the number minus three times the reciprocal of the number is equal to 1?

marshall27 [118]

Solve:

"<span>twice the number minus three times the reciprocal of the number is equal to 1."
3(1)
Let the number be n. Then 2n - ------- = 1
n

Mult all 3 terms by n to elim. the fractions:

2n^2 - 3 = n. Rearranging this, we get 2n^2 - n - 3 = 0.

We need to find the roots (zeros or solutions) of this quadratic equation.

Here a=2, b= -1 and c= -3. Let's find the discriminant b^2-4ac first:

disc. = (-1)^2 - 4(2)(-3) = 1 + 24 = 25.

That's good, because 25 is a perfect square.
-(-1) plus or minus 5 1 plus or minus 5
Then x = ------------------------------ = --------------------------
2(2) 4

x could be 6/4 = 3/2, or -5/4.

You must check both answers in the original equation. If the equation is true for one or the other or for both, then you have found one or more solutions.</span>

8 0

3 years ago

A parallelogram with four right angles? Which one is it??

Sliva [168]

Y is the answer for four right angles

8 0

2 years ago

Read 2 more answers

I need help on 34 and 36

aleksley [76]

34. 65 = 3/4c - 7....add 7 to both sides
65 + 7 = 3/4c...simplify
72 = 3/4c...multiply both sides by 4/3, eliminating the 3/4 on the left
72 * 4/3 = c
288/3 = c
96 = c

36. -5/2 = 3/4z + 1/2 ...subtract 1/2 from both sides
-5/2 - 1/2 = 3/4z .... simplify
-6/2 = 3/4z ....reduce
-3 = 3/4z....multiply by 4/3. eliminating the 3/4 on the left
-3 * 4/3 = z
-12/3 = z
-4 = z

4 0

3 years ago

My brother wants to estimate the proportion of Canadians who own their house.What sample size should be obtained if he wants the

AVprozaik [17]

Answer:

a) $n=\frac{0.675(1-0.675)}{(\frac{0.02}{1.64})^2}=1475.07$

And rounded up we have that n=1476

b) $n=\frac{0.5(1-0.5)}{(\frac{0.02}{1.64})^2}=1681$

And rounded up we have that n=1681

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{\hat p(1-\hat p)}{n}})$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

If solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

Part a

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 90% of confidence, our significance level would be given by $\alpha=1-0.9=0.1$ and $\alpha/2 =0.05$ . And the critical value would be given by:

$z_{\alpha/2}=\pm 1.64$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.02$ and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

And replacing into equation (b) the values from part a we got:

$n=\frac{0.675(1-0.675)}{(\frac{0.02}{1.64})^2}=1475.07$

And rounded up we have that n=1476

Part b

For this case since we don't have a prior estimate we can use $\hat p =0.5$

$n=\frac{0.5(1-0.5)}{(\frac{0.02}{1.64})^2}=1681$

And rounded up we have that n=1681

8 0

2 years ago

The graph below is a portion of a complete graph. Which graph below is the complete graph assuming it is an even function?

Ierofanga [76]

Answer:

Option b

Step-by-step explanation:

A function is even if and only if f(-x) = f(x).

This means that there is the same value of y for $x_0$ and for $-x_0$

Where $x_0$ is any point belonging to the function .

Therefore you must select a graph whose ordered pairs are of the form $(x_0, y_0)$ and $(-x_0, y_0)$

Therefore the correct answer is option b. Assume that each box in the graph equals 1 unit. Then, for x = 2 y = -3 and for x = -2 y = -3. Then it is shown that the function is even.

8 0

3 years ago