the lenght of a rectangle is 2 cm less than 7 times the width. the perimeter is 60 cm . find the width and lenght

Answers

Answer 1

Answer: First, you want to establish your equations.

L=7W-2
P=60

This is what we already know. To find the width, we have to plug in what we know into P=2(L+W), our equation to find perimeter.

60=2(7W-2+W)

Now that we only have 1 variable, we can solve.

First, distribute the 2.
60=14W-4+2W

Next, combine like terms.

60=16W-4

Then, add four to both sides.

64=16W

Lastly, divide both sides by 16

W=4

To find the length, we plug in our width.

7W-2

7(4)-2

28-2

L=26

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Mrs.Traynor's class is taking a field trip to the zoo.The trip cost $26 for each student.There are 22 students in her class.Round each factor to estimate the total cost of the students field trip,

Answers

so they said each is $26 and students is 22
like you need to do multiply 26*22=572
so she get $572 for 22 students.

Describe how to find the least common multiple of three number .

Answers

Take the three numbers, and list all of their prime factors. I'll use 3, 9, and 21 for an example to help.
3: 3
9: 3 x 3
21: 7 x 3
You take the times that a number occurs the most in any of the three numbers and multiply them together. 3 occurs the most in a single number twice, and 7 occurs the most in a number once.
So you'd multiply 3 x 3 x 7 to get 63.

Y =3x -1 has a gradient of 3. Write the equation of a line parallel to itPlease tell me the answer and how to do this

Answers

-3x+1 just do the opposite

I need help um i dont need to to my work or check my answer justAs you can see, I can figure out the problems fine, its explaining how the solution is related to the situation. If you could help, or if you see any problems with my work, it would be very appreciated. Thank you for your time.

Answers

3.
area=legngth tiimes width
legnth is 10 more than 2 times width
l=10+2w
lw=area=(10+2w)w=10w+2w^2
area=3600
3600=10w+2w^2
so divide by 2
1800=5w+w^2
subtract 1800 from both sides
(note they used x instead of w)
0=w^2+5w-1800
then the facotred form is (w-40)(w+45)=0

0 product property measn if you have xy, then x and or y =0

therefor
w-40=0 and w+45=0
w=40 or -45
discard negative because negative legnth is not possible

explian how solution relates to situation
it is math so it is correct because we represented it corrrectly

the other solution is because of math and eliminate negative legnth becasue tha tis not possible
basically because we represented it correctly
not a very clear quetion to answer

basically 'because it represents the solution so we solved it and it is correct'

#3:
In the first paragraph, the equation is x² + 5x - 1800 = 0 .
Here's where this equation comes from:
Call the width of the park 'x'.
Then, according to the question, the length is (2x + 10).
When you multiply (width) x (length) to get the area, and
simplify the product, it turns out that   x² + 5x - 1800 = 0 .
But don't forget . . . 'x' started out being the width, and when
you figure out what 'x' is, that'll be the width of the dog park.

3.a). is factoring the equation, getting ready to solve it.

3.b). is finding the solutions for 'x' from the factored form.
   Remember that every quadratic equation has two solutions.
   In this one, they are x = 40 and x = -45 .

   'x' is the width of the dog park. Can it be both values ?
   Can it be only one of them ? Can it be 40 ? How about -45 ?

3.c). 'x' is the width of the real dog park. In the real world, there's
   no way the city engineers can build it with a negative width.
   That would be totally silly. So the real width 'x' = 40 yards.

   Now look way back at the question:
   "The length of the park is 10 more than twice the width."

   The width is 40 yards.
   Twice the width is 80 yards.
   10 more than that is 90 yards.
==> The length is 90 yards.

   Now we have (length = 90 yards) and (width = 40 yards).

   How do we know if these are correct ?
   Well, let's use them to calculate the area.

Area = (length) x (width)
   = (90 yards) x (40 yards) = 3,600 square yards.

   That's what the question said !
   We got the right numbers ! yay !
_______________________________________________

#4
This one is very similar to the dog park in many ways.

Again, in the first paragraph, the signs are missing from the
equation. The correct equation is:    x² + 6x - 55 = 0 .

This is also a tricky question, because some of the information
in the first paragraph is only there to confuse you. That business about "... increase both the height and the width ... by 3 inches."
You don't need that ! It may come up in #5, I don't know. But here
in #4, it never asks anything about it, and you don't need to know it.
All you need to know is that it's a "square image". That does that
tell you ? It tells you that the height and width are equal !
That's why the equation x² + 6x - 55 = 0  "can be used to find the
height and width of the original image" . They're both the same.

4.a). is factoring the equation, getting ready to solve it.

4.b). is finding the solutions for 'x' from the factored form.
   Remember that every quadratic equation has two solutions.
   In this one, they are x = 5 and x = -11 .

   'x' is a dimension of the image. Can it be either value ?
   Can it be only one of them ? Can it be 5 ? How about -11 ?

4.c). 'x' is a dimension of the real image. In the real world,
   there's no way the graphic designer can start with an image
   that has a negative dimension. That would be totally silly.

So the real dimension of the image is 5 inches.
      Since it's square, the length and width are both 5 inches.
________________________________________

Now I'll just bet that there's another problem coming along to
ask you what the area of the new, bigger image is going to be,
after he increases both the height and the width of the image
by 3 inches. You don't need to worry about crossing that
bridge until you come to it.

Which out of these numbers has the same absolute value as one another and please help I don't really understand absolute value

Answers

Answer:

Step-by-step explanation:Absolute value is a number's distance away from zero. For example, on a number line, -9 is 9 spaces away from zero. So, the absolut value is 9. Similarly, the number 9 is also 9 spaces from zero, so the absolute value would be 9. 9 and -9 both have an absolute value of 9. I hope this is helpful!

-32, 32. Absolute value is this distance away from 0 the number is

What is the value of the expression? -2/5 - 3/7 * 7/10 = A. -7/10

B. -1/3

C. 1/3

D. 7/10

Answers

order of operations
PEMDAS
parenthasees
exponents
multipication or division whichever comes first
addition or subtraction whichere comes first

first muliplication
-3/7 times 7/10=-21/70=-3/10

then we have
-2/5-3/10
make bottom number 10
-2/5=-4/10
-4/10-3/10=-7/10

answer is A

-(2\5)-(3\7)*(7\10)=-(2\5)-3\10=-4\10-3\10=-7\10.

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