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3 years ago

The perimeter of a square is 28x – 4.

Mathematics

1 answer:

Scorpion4ik [409]3 years ago

8 0

Answer:

Step-by-step explanation:

Divide both 28x and -4 by 4 because a square has 4 equal sides. That comes out to 7x-1, therefore answer B is correct.

You might be interested in

Simplify x+ -4x + -3

Flura [38]

Answer:

-3

Step-by-step explanation:

X+-4x=3

4 0

3 years ago

Read 2 more answers

Xanthia can read 100 pages per hour and Molly can read 50 pages per hour. If they each read the same book, and the book has 225

Talja [164]

Answer:

135 minutes

Step-by-step explanation:

Let

y -----> the number of pages to finish reading the book

x ----> the number of hours

we know that

The linear equation in slope intercept form is equal to

$y=mx+b$

where

m is the unit rate or slope of the linear equation

b is the y-intercept or initial value

In this problem we have

<em>Xanthia</em>

$m=100\ pages/hour$

$b=225\ pages$

$y=-100x+225$ ----> the slope is negative because is a decreasing function

For y=0

substitute and solve for x

$0=-100x+225$

$100x=225$

$x=2.25\ hours$ ---> Xanthia's time to finish reading the book

<em>Molly</em>

$m=50\ pages/hour$

$b=225\ pages$

$y=-50x+225$ ----> the slope is negative because is a decreasing function

For y=0

$0=-50x+225$

$50x=225$

$x=4.5\ hours$ --- Molly's time to finish reading the book

To find out how many more minutes than Xanthia would it take for Molly to finish reading the book, subtract Xanthia's time from Molly's time

$4.5\ h-2.25\ h=2.25\ h$

Convert to minutes

Multiply by 60

$2.25\ h=2.25(60)=135\ minutes$

4 0

3 years ago

Read 2 more answers

Can someone help me answer this answer and explanation plz I’ll give your brainlist and points

JulijaS [17]

Answer:

1A. C B E D A F

B. H G J K I L

Step-by-step explanation:

6 0

3 years ago

Using a sheet of graph paper, solve the following system of equations graphically. Be sure to show any work, use a straight edge

madam [21]

Answer:

Step-by-step explanation:

Given system is

$\left \{ {{x+y=0} \atop {x-y+2=0}} \right.$

If we graph, the solution would be the interception point between these two lines, because each linear equation represents a line. The lines are attached.

In the graph, you can observe that the solution is the point (-1,1), that is x = -1 and y = 1.

Now, if we want to solve this system by another method, we can just sum both equations and solve for <em>x</em>

$\left \{ {{x+y=0} \atop {x-y+2=0}} \right.$

$2x+2=0\\x=\frac{-2}{2}=-1$

Then, we replace this value in one equation to find the other value

$x+y=0\\-1+y=0\\y=1$

Therefore, the solution is (-1,1)

4 0

3 years ago

The amount of time that a customer spends waiting at an airport check-in counter is a random variable with mean 8.0 minutes and

strojnjashka [21]

Answer:

P ( 5 < X < 10 ) = 1

Step-by-step explanation:

Given:-

- Sample size n = 49

- The sample mean u = 8.0 mins

- The sample standard deviation s = 1.3 mins

Find:-

Find the probability that the average time waiting in line for these customers is between 5 and 10 minutes.

Solution:-

- We will assume that the random variable follows a normal distribution with, then its given that the sample also exhibits normality. The population distribution can be expressed as:

X ~ N ( u , s /√n )

Where

s /√n = 1.3 / √49 = 0.2143

- The required probability is P ( 5 < X < 10 ) minutes. The standardized values are:

P ( 5 < X < 10 ) = P ( (5 - 8) / 0.2143 < Z < (10-8) / 0.2143 )

= P ( -14.93 < Z < 8.4 )

- Using standard Z-table we have:

P ( 5 < X < 10 ) = P ( -14.93 < Z < 8.4 ) = 1

7 0

3 years ago