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3 years ago

I need help marking brainliest

Mathematics

2 answers:

Furkat [3]3 years ago

7 0

Answer: 2

Explanation: 1 makes no sense. With 3 there would still be the pollution to worry about and there’s the same problem with 4. Because there is more pollution the cricket frogs would die out.

saw5 [17]3 years ago

3 0

Answer:

2) Decreases as the habitat is increasingly polluted

Step-by-step explanation:

number 1 make no sense. 3; at the start, say the population is x. but taking into account the pesticide, it cant no longer ramain the same (pesticide kills some of the x) . 4; similar to the case for answer 3

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Sammy is conducting a science experiment were he has to mix 8. 25 ounces and 430 ounces of lemon juice. How many ounces will he

djyliett [7]

438.25 ounces altogether.

5 0

4 years ago

An x-method chart shows the product a c at the top of x and b at the bottom of x. Above the chart is the expression a x squared

Bond [772]

Answer:

The other factor is (x + 2).

Step-by-step explanation:

If x - 10 is a factor of x^2 - 8x - 20 then we must find another factor that includes +2x, so that we have -10x + 2x = -8x. That factor is (x + 2):

x^2 - 8x - 20 = (x - 10)(x + 2)

As a test, multiply -10 and +2. We get -20, matching the constant of the given polynomial. Also, -10x + 2x = -8x, another match.

9 0

3 years ago

Read 2 more answers

8-35. Use your knowledge of polygons to answer the questions below, if possible.

Nataliya [291]

Answer:

(a)I. 13 Sides II. 7 Sides

(b) 4 Sides, Square

(c)x=52 degrees

(d)x=107 degrees

(e)1620 degrees

Step-by-step explanation:

(a)The Sum of the Interior angle of polygon with n sides is derived using the formula: (n-2)180.

I. If the Interior angle is $1980^0$

Then:

$(n-2)180^0=1980^0\\$Divide both sides by 180^0 $ to isolate n$\\n-2=11\\$Add 2 to both sides of the equation\\n-2+2=11+2\\n=13$

The polygon has 13 sides.

II. If the Interior angle is $900^0$

Then:

$(n-2)180^0=900^0\\$Divide both sides by 180^0 $ to isolate n$\\n-2=5\\$Add 2 to both sides of the equation\\n-2+2=5+2\\n=7$

The polygon has 7 sides.

(b)The sum of the exterior angle of a polygon is 360 degrees,

Each exterior angle of a n-sided regular polygon is: $\frac{360^0}{n}$

If the exterior angle of a regular polygon is 90°

Then:

$90\°=\frac{360^0}{n}\\ 90n=360\\n=4$

The regular polygon has 4 sides and it is called a Square.

(c)The Sum of the Interior angle of polygon with n sides is derived using the formula: (n-2)180.

Each Interior angle of a regular n-sided polygon is: $\frac{(n-2)180^0}{n}$

For a pentagon, n=5

Then:

$\frac{(5-2)180^0}{5}=2x+4\\108=2x+4\\108-4=2x\\104=2x\\x=52^0$

(d)The sum of the exterior angle of a polygon is 360 degrees.

If four of the exterior angles of a pentagon are 57, 74, 56, and 66.

Let the fifth angle=x

Then:

$57+74+56+66+x=360^0\\253+x=360\\x=107^0$

(e)The Sum of the Interior angle of polygon with n sides is derived using the formula: (n-2)180.

In an 11-gon., n=11

Therefore, the sum of the interior angle=(11-2)180= $1620^0$

The sum of the interior angle does not change either in a regular or irregular polygon.

3 0

3 years ago

Helppp pt.5 plzzzzz

Fiesta28 [93]

Answer: 60 cm²

Step-by-step explanation:

This is pretty simple, we know AB is 12 cm and DE is 4 cm. We know ABC has a total of 180 square centimeters. So...

12 ÷ 3 = 4

180 ÷ 3 = 60

The answer is 60 cm²

I hope this helps!

6 0

3 years ago

Amanda went to the store to purchase ink pens. She found three kinds of pens. The first cost $4 each; the price of the second ki

KonstantinChe [14]

Answer:

Amanda buy first kind of pen = 3

Amanda buy second kind of pen = 2

Amanda buy third kind of pen = 15

Step-by-step explanation:

Given - Amanda went to the store to purchase ink pens. She found three

kinds of pens. The first cost $4 each; the price of the second kind

was 4 for $1; and the cost for the third kind was 2 for $1. She bought

20 pens and she bought at least one of each kind. (It is possible to

buy only 1 of the pens that are "4 for $1" or "2 for $1".) The cost was

$20.

To find - When she got back to her office, Amanda decided to turn this into

a math problem for me. She asked: how many of each kind did I

buy?

Proof -

Let Amanda buy first kind of pen = x

second kind of pen = y

third kind of pen = z

As given,

She bought total pen = 20

⇒x + y + z = 20 ...............(1)

Now,

As given,

cost for first kind pen = $4 for 1 pen

As she bought x pens of first kind , so

Cost of x pens of first kind = $4x

Now,

The price of the second kind was 4 for $1

⇒Cost of second kind = $ $\frac{1}{4}$ for 1 pen

As she bought y pens of send kind , so

Cost of y pens of second kind = $ $\frac{1}{4}y$

Now,

The price of the third kind was 2 for $1

⇒Cost of third kind = $ $\frac{1}{2}$ for 1 pen

As she bought z pens of send kind , so

Cost of z pens of third kind = $ $\frac{1}{2}z$

Now,

As given, The cost was $20

⇒4x + $\frac{1}{4}y$ + $\frac{1}{2}z$ = 20

⇒16x + y + 2z = 80 .....................(2)

∴ we get 2 equations

x + y + z = 20 .....................(1)

16x + y + 2z = 80 .....................(2)

Now,

Subtract equation (1) from equation (2) , we get

16x + y + 2z - ( x+ y + z )= 80 - 20

⇒16x + y + 2z - x - y - z = 60

⇒15x + z = 60

⇒z = 60 - 15x

Now,

Put the value of z in equation (1) , we get

x + y + 60 - 15 x = 20

⇒ y - 14x = 20 - 60

⇒y - 14x = -40

⇒14x - y = 40

⇒y = 14x - 40

Now,

we get

z = 60 - 15x

y = 14x - 40

As given

she bought at least one of each kind

it means x > 1, y > 1, z > 1

Now,

If x = 1, then y = 14 - 40 = -26

Not possible

If x = 2 , then y = 14(2) - 40 = -12

Not possible

If x = 3, then y = 14(3) - 40 = 2 and z = 60 - 15(3) = 15

Possible.

If x = 4, then y = 14(4) - 40 = 16 and z = 60 - 15(4) = 0

Not Possible.

If x = 5, then y = 14(5) - 40 = 30 and z = 60 - 15(5) = -15

Not Possible.

∴ we get

x = 3, y = 2, z = 15

Amanda buy first kind of pen = x = 3

Amanda buy second kind of pen = y = 2

Amanda buy third kind of pen = z = 15

7 0

3 years ago