Pls help ill give brainliest pls dont answer if you dont know thanks

4a-b<br> Evaluate the expression when a=5 and b=-7

stepladder [879]

Answer:

27

Step-by-step explanation:

So first we need to plug in 5 as the variable a and -7 as the variable b

4(5)-(-7)

Next we multiply the 4 and the 5 together to get 20

4(5) = 20 or 4 x 5 = 20

20-(-7)

Now we subtract negative 7 from 20

20-(-7) = 27

This can also be written as 20 plus 7 as a mathematical rule states: two negatives make a positive. So:

20-(-7) = 20 + 7

Both of these are equivalent in every sense of the word and give us our final answer of 27

8 0

3 years ago

Read 2 more answers

Could the value of x in the figure below be 10?

RSB [31]

Answer:

It cannot

Step-by-step explanation:

The hypotenuse is always the longest side, which in this instance of the left triangle, it is 14

If x were to be 10, this would make line KM to be 15 units long, (10 + 5)

Despite line LM being unknown, x must have a number below 10 (, and 9) to make it possible

6 0

3 years ago

Mark u brainliest and give 30 points.No random answers and pls give answers with explanation/steps or i will report u.

blagie [28]

Answer:

I use equal signs throughout but they are meant to be less than or equal to signs.

s=sandwiches

4.5s+6 less than or equal to 50

The answer is s is less than or equal to 12

Step-by-step explanation:

Finding Inequality

1. we know everything costs 50 in total so that is on one side of the equal sign.

____=50

2. we know he already spent 6 dollars so the money he can spend is 6 dollars less.

____+6=50

3. Each sandwich costs 4.50 $ so how much money does he have left to spend? we figure that out by multiplying the price by the number of sandwiches.

4.5s+6=50

Solving

1. 4.5s-6=50

First use the addition property of equality and add 6 to both sides.

2. 4.5s=56

Then use the division property of equality and divide each side by 4.5

3. you get a decimal but since you can't buy half a sandwich the answer is

s is less than or equal to 12

3 0

3 years ago

Spaulding is the leading maker for basketballs in the US. Spaulding prides itself on the quality that its basketballs have the r

Vesna [10]

Answer:

0 < 0.05, which means that we reject the null hypothesis, meaning that the air pressure of the balls is different of the target value of 7.9.

Step-by-step explanation:

The air pressure of a particular ball has a target value of 7.9 PSI.

This means that the null hypothesis is:

$H_{0}: \mu = 7.9$

The alternate hypothesis is:

$H_{a}: \mu \neq 7.9$

The test statistic is:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

In which X is the sample mean, $\mu$ is the value tested at the null hypothesis, $\sigma$ is the standard deviation and n is the size of the sample.

The hypothesis tested means that $\mu = 7.9$

Suppose the basketballs have a normal distribution with a standard deviation of 0.20 PSI.

This means that $\sigma = 0.2$

When a shipment of basketballs arrive, the consumer takes a sample of 21 from the shipment and measures their PSI to see if it meets the target value, and finds the mean to be 7.3 PSI.

This means that $X = 7.3, n = 21$

The test statistic is:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

$z = \frac{7.3 - 7.9}{\frac{0.2}{\sqrt{21}}}$

$z = -13.74$

pvalue:

We are testing that the mean pressure is different than the target value of 7.9, and since the test statistic is negative, the pvalue is 2 multiplied by the pvalue of z = -13.74, which we find looking at the z-table.

$z = -13.74$ has a pvalue of 0.

2*0 = 0

0 < 0.05, which means that we reject the null hypothesis, meaning that the air pressure of the balls is different of the target value of 7.9.

8 0

3 years ago

If a person draws 2 cards at random from a standard deck of 52 cards, what is the probability that they get 2 aces?

dangina [55]

Answer:4/52=1/13

Step-by-step explanation:

The deck has 52 cards and contains 4 aces. When you draw a card, the probability of drawing an ace is 4/52=1/13

8 0

4 years ago