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2 years ago

Solve the system of equations x+y=-1 and 5x-7y=79 by combining the equations.

Mathematics

1 answer:

Leya [2.2K]2 years ago

6 0

9514 1404 393

Answer:

(x, y) = (-6, -7)

Step-by-step explanation:

Multiply the first equation by 7 and add that to the second.

7(x +y) +(5x -7y) = 7(-1) +(79)

12x = 72

x = 6

y = -1 -x = -1 -6 = -7

The solution is (x, y) = (6, -7).

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MATH!!! find the volume of the pyramid. pleaseee answer correctly and tell me how you got your answer.

bagirrra123 [75]

The area of polygons formulas to V=2.56m^2

We have to determine,

The volume of the pyramid.

<h3>What is the volume of the pyramid?</h3>

The volume of a pyramid is found using the formula,

V = (1/3) Bh

where 'B' is the base area and 'h' is the height of the pyramid.

hight =2.4m

base=1.4+1.8

base=3.2m

V = (1/3) (3.2)(2.4)

V=2.56m^2

As we know the base of a pyramid is any polygon,

we can apply the area of polygons formulas to find 'B.

V=2.56m^2.

To learn more about the volume visit:

brainly.com/question/1972490

#SPJ1

3 0

2 years ago

What will be the area of the given shape? (please help)

Leni [432]

Answer:

620

Step-by-step explanation:

To find the area of strangely-shaped structures, like this one, it is easiest if we cut the shape into smaller, more recognizable, shapes..

We can first cut off the top/center rectangle of this shape , which has a width of 10, and a length of 12. The "area" is length × width.

So, we multiply 12 × 10 to find the area of this section.

12 × 10 = 120

if we look at the bottom half, we can see that there is an identical rectangle (because it has the same width of 10 and length of 12) ! So, we can simply add 120 to our total twice to count both of these areas.

(when putting areas of multiple portions together, we add--not multiply)

120 (first/top rectangle)

+ 120 (lower rectangle)

_______________

240

So, our area so far is 240.

Now, we need to find the horizontal (left-right) section of this shape.

We can see that it has a width of 10 (look at the right end), and a length of 38 14 + 10 + 14 (38 total)

So, to find the area of this portion, we will multiply its length × width, which we know is: 38 × 10

38 × 10 = 380.

So, we can now add our areas together:

240

+ 380

__________

620

So, our area of this shape is 620

6 0

1 year ago

Read 2 more answers

Please help? :(

viva [34]

Answer:

This is a easy question you can find the answer online. It was on a state exam and all the answers and work is shown how to do it.

Step-by-step explanation:

6 0

3 years ago

Hardy is packing his book collection into a box. Each book measures 4in by 6in by 1 inch. The box he uses measures 24in by 24in

liberstina [14]

Answer:

1. 192 books.

2. 96 books.

3. 24 books.

Step-by-step explanation:

1. Let's find the volume of each book and the volume of the box, this way:

Volume of a book = 4 * 6 * 1 = 24 inches ³

Volume of the box = 24 * 24 * 8 = 4,608 inches ³

2. If Hardy fills the box completely, what is the greatest number of books that fit into the box?

Greatest number of books = Volume of the box/Volume of a book

Greatest number of books = 4,608/24

Greatest number of books = 192

3. If Hardy fills the box completely with the least number of layers, there will be (blank) books on the bottom layer.

The height of the box is 8 inches, so it can only can hold 2 or 8 layers of books, since the books are 4 * 6 * 1 inches.

Greatest number of layers = Height of the box/Width of a book

Greatest number of layers = 8/1 = 8

Minimum number of layers = Height of the box/Height of a book

Minimum number of layers = 8/4 = 2

Upon saying that, we have:

Number of books per layer = Greatest number of books/Minimum number of layers

Number of books per layer = 192/2 = 96

4. To fill the box completely, Hardy places 8 layers of books in the box. There are (blank) books in each layer.

Number of books per layer = Greatest number of books/Number of layers

Number of books per layer = 192/8

Number of books per layer = 24

5 0

3 years ago

The function below shows the number of car owners f(t), in thousands, in a city in different years t:

Alenkasestr [34]

The Average Rate of Change is the change of the function's value to the change in the variable t along some close interval

$f(t) = 1.1~t^2 - 2.5t + 1.5\\~\\f(5)=1.1~(5)^2 - 2.5(5) + 1.5=16.5\\~\\~\\f(3)=1.1~(3)^2 - 2.5(3) + 1.5=3.9\\~\\~\\ARC= \frac{f(5)-f(3)}{5-3} = \frac{16.5-3.9}{5-3} =6.3$

I hope that helps!

3 0

3 years ago