The slope of a line perpendicular to y=4x-7 is

John went on a trip. 2 hours in he a 15 gallons of gas in her tank.7 hours into her trip she had 3 gallons left. Find the rate o

maks197457 [2]

Answer:

jjjjjjajjajajajhahahahajahajjaha

5 0

2 years ago

How to do the substitution in math?

seraphim [82]

Substitution method can be applied in four steps

Step 1:

Solve one of the equations for either x = or y = .

Step 2:

Substitute the solution from step 1 into the other equation.

Step 3:

Solve this new equation.

Step 4:

Solve for the second variable.

hope this helps you!

4 0

3 years ago

1. (k+7)² =289 2. (2s-1)² =225 3. (x-4)² =169 please help me answer these :)

professor190 [17]

$(k+7)^2 =289\\
|k+7|=17\\
k+7=17\vee k+7=-17\\
k=10 \vee k=-24$

$(2s-1)^2 =225\\
|2s-1|=15\\
2s-1=15\vee 2s-1=-15\\
2s=16 \vee 2s=-14\\
s=8 \vee s=-7$

$(x-4)^2 =169\\
|x-4|=13\\
x-4=13 \vee x-4=-13\\
x=17 \vee x=-9$

6 0

3 years ago

Read 2 more answers

Find the product.

4vir4ik [10]

Answer :

$6{y}^{4} {z}^{2} + 12 {y}^{3} {z}^{2}-3 {y}^{3} {z}+3 {y}^{2} {z}^{2}$

Step-by-step explanation :

To find the product of

$3 {y}^{2} z(2 {y}^{2} z + 4yz - y + z)$

First we expand the bracket ,

it implies that, we use the expression outside the bracket to multiply individual expressions inside the bracket.

Hence

$3 {y}^{2} z(2 {y}^{2} z + 4yz - y + z)$

$= 3 {y}^{2} z(2 {y}^{2} z) + 3 {y}^{2} z(4yz) - 3 {y}^{2} z(y )+3 {y}^{2} z( z)$

we now apply the law of indices

${a}^{m} \times {a}^{n} = {a}^{m+n}$

meaning, when you are multiplying two expressions with the same bases , repeat one of the bases and add the exponents.

Then, simplify to obtain

$= 6{y}^{4} {z}^{2} + 12 {y}^{3} {z}^{2}-3{y}^{3} {z}+3 {y}^{2} {z}^{2}$

3 0

2 years ago

In a survey of adults aged 57 through 85 years, it was found that 86.6% of them used at least one prescription medication. Com

OleMash [197]

Answer:

a) 272 used at least one prescription medication.

b) The 90% confidence interval estimate of the percentage of adults aged 57 through 85 years who use at least one prescription medication is (85.6%, 87.6%).

Step-by-step explanation:

Question a:

86.6% out of 3149, so:

0.866*3149 = 2727.

272 used at least one prescription medication.

Question b:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the z-score that has a p-value of $1 - \frac{\alpha}{2}$ .

For this problem, we have that:

$n = 3149, \pi = 0.866$

90% confidence level

So $\alpha = 0.1$ , z is the value of Z that has a p-value of $1 - \frac{0.1}{2} = 0.95$ , so $Z = 1.645$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.866 - 1.645\sqrt{\frac{0.866*0.134}{3149}} = 0.856$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.866 + 1.645\sqrt{\frac{0.866*0.134}{3149}} = 0.876$

For the percentage:

0.856*100% = 85.6%

0.876*100% = 87.6%.

The 90% confidence interval estimate of the percentage of adults aged 57 through 85 years who use at least one prescription medication is (85.6%, 87.6%).

7 0

3 years ago