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2 years ago

Please help me . With explanation:)

Mathematics

1 answer:

zhuklara [117]2 years ago

6 0

<h3>Answer: 35</h3>

===============================================================

Explanation:

To start off, we'll find the circumference of the full circle. We'll ignore the black and yellow sectors.

C = 2*pi*r

C = 2*pi*7

C = 14pi

This is the exact distance around the full circle in terms of pi

However, we don't want the the full circular perimeter. Instead, we only want the portions that are along the black sectors. The yellow sectors have central angle 24 degrees each. This takes up 3*24 = 72 degrees overall because the three regions have equal area and equal central angle.

Subtract that from 360:

360-72 = 288

The yellow regions take up 72 degrees while the remaining black sectors take up a combined 288 degrees.

------------------------------

Why is 288 useful? Because it helps set up the fraction 288/360 to represent the portion of the perimeter that we care about.

(288/360)*14pi = 35.1858 mm approximately

This rounds to 35 mm

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B=3 V/h I’m supposed to solve the question for V.

FromTheMoon [43]

Answer:
V=Bh/3

Explanation:
B=3V/h
1) Multiply h on both sides.
Bh=3v
2) Divide both sides by 3
Bh/3=V

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2 years ago

Thank u so much much appreciated

attashe74 [19]

Answer:

Step-by-step explanation:

The definition of a parrelelogram is "a four-sided plane rectilinear figure with opposite sides parallel". Since you already know that EH and Fg are equal because of the black ticks on them. Now you only need to find out wheter or not EF≅HG to meet the criteria of a parrelologram.

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3 years ago

Problems 2.21, 2.22, 2.23

RoseWind [281]

Statements can be proved by contrapositive, contradiction or by induction.

2.21 and 2.23 are proved by contrapositive
2.22 is proved by induction

2.21: If $n^3$ is even, then n is even (By contrapositive)

The contrapositive of the above statement is that:

If n is odd, then $n^3$ is odd

Represent the value of n as:

$n = 2k + 1$ , where $k \ge 0$

Take the cube of both sides

$n^3 = (2k + 1)^3$

Expand

$n^3 = 8k^3 + 6k^2 + 6k + 1$

Group

$n^3 =[ 8k^3 + 6k^2 + 6k] + 1$

Factor out 2

$n^3 =2[4k^3 + 3k^2 + 3k] + 1$

Assume w is an integer; where:

$w =4k^3 + 3k^2 + 3k$

So, we have:

$n^3 =2w + 1$

The constant term (i.e. 1) means that $n^3$ is odd.

Hence, the statement has been proved by contrapositive.

i.e. If n is odd, then $n^3$ is odd

2.22 $3n + 4$ is even, if and only if n is even

We have: $3n + 4$

Assume that: $n = 2k + 2$ for $k \ge 0$

So, we have:

$3n + 4 = 3(2k + 2) + 4$

Open bracket

$3n + 4 = 6k + 6 + 4$

$3n + 4 = 6k + 10$

Factorize

$3n + 4 = 2(3k + 5)$

The factor of 2 means that $3n + 4$ is even.

Hence, $3n + 4$ is even, if and only if n is even

2.22: $s \ne -1$ and $t \ne -1$ , then $s + t + st \ne -1$

To do this, we prove by contrapositive.

The contrapositive of the above statement is:

If $s = -1$ and $t=-1$ , then $s + t + st = -1$

We have:

$s + t + st = -1$

Substitute the values of s and t in: $s + t + st = -1$

$-1 -1 -1 \times -1 = -1$

$-1 -1 + 1 = -1$

$-1 = -1$

Hence, by contrapositive:

If $s = -1$ and $t=-1$ , then $s + t + st = -1$

Read more about proofs at:

brainly.com/question/19643658

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3 years ago

Is 3x+2y=8 a quadratic equation?

Ierofanga [76]

Answer:

No.

Step-by-step explanation:

No, it is a linear equation. There are no exponents on the x or y variables.

7 0

2 years ago

Does anyone know how to do this?? Help please!!!!

Doss [256]

Answer:

When we have a rational function like:

$r(x) = \frac{x + 1}{x^2 + 3}$

The domain will be the set of all real numbers, such that the denominator is different than zero.

So the first step is to find the values of x such that the denominator (x^2 + 3) is equal to zero.

Then we need to solve:

x^2 + 3 = 0

x^2 = -3

x = √(-3)

This is the square root of a negative number, then this is a complex number.

This means that there is no real number such that x^2 + 3 is equal to zero, then if x can only be a real number, we will never have the denominator equal to zero, so the domain will be the set of all real numbers.

D: x ∈ R.

b) we want to find two different numbers x such that:

r(x) = 1/4

Then we need to solve:

$\frac{1}{4} = \frac{x + 1}{x^2 + 3}$