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3 years ago

ABCDE is aregular pentangon X=?

Mathematics

1 answer:

Viefleur [7K]3 years ago

6 0

Answer:

x = 5.2

Step-by-step explanation:

Measure of interior angle of a regular polygon = $\frac{(n-2)\times180}{n}$

Here n = number of sides of the polygon

Interior angle of a regular pentagon = $\frac{(5-2)\times180}{5}$

= 108°

By applying cosine rule in ΔABK,

(BK)² = (AK)² + (AB)² - 2(AK)(AB)cos(108)°

(x + 3)² = 4² + 6² - 2(4)(6)cos(108)°

x² + 6x + 9 = 16 + 36 - (-14.83)

x² + 6x = 57.83

x² + 6x - 57.83 = 0

x = $\frac{-6\pm \sqrt{6^2-4(1)(-57.83)}}{2(1)}$

x = $\frac{-6\pm16.35}{2}$

x ≈ -11.2, 5.2

Since, x can't be negative,

x = 5.2 will be the answer.

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Winslow plans to grow 12 kinds of vegetables in her garden. She has 34 seeds of each kind of vegetables. A neighbor gives her 10

ExtremeBDS [4]

Answer: 658

Step-by-step explanation:

If Winslow wants to plant 12 vegetables and has 34 seeds of each kind of vegetable, then she has 12*34 seeds.

12*34=408

If a neighbor giver her 10 more packets, each with 25 seeds, she has 10*25 more seeds.

10*25=250

Then we add 408+250 to get 658 seeds

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3 years ago

Factor 18s-63 A 9(2s+7) B 6(3s-11) C 18(s-3) D 9(2s-7)

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Answer:

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Step-by-step explanation:

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3 years ago

Which equation can be solved by using this expression?

Marat540 [252]

Answer:

The correct answer option is B. 2 = 3x + 10x^2

Step-by-step explanation:

We are to determine whether which of the given equations in the answer options can be solved using the following expression:

$x=\frac{-3 \pm\sqrt{(3)^2+4(10)(2)} }{2(10)}$

Here, $a = 10, b = 3$ and $c=-2$ .

These requirements are fulfilled by the equation 4 which is:

$12=3x+10x^2$

Rearranging it to get:

$10x^2+3x-2=0$

Substituting these values of $a,b,c$ in the quadratic formula:

$x= \frac{-b \pm \sqrt{b^2-4ac} }{2a}$

$x= \frac{-3 \pm\sqrt{(3)^2-4(10)(-2)} }{y}$

3 0

3 years ago

You buy a bookshelf. The label on the box says the bookshelf is 51 inches tall. How tall is it in feet?

user100 [1]

A feet is 12 inches.

$51/12=4.25$

The bookshelf is 4 feet, 3 inches.

6 0

3 years ago

Read 2 more answers

(-3,y), (-9,-2); m=1

12345 [234]

Answer:

The value of y is 4

The equation of line is y = x + 7 .

Step-by-step explanation:

Given as :

The points are

( $x_1$ , $y_1$ ) = (- 3, y)

( $x_2$ , $y_2$ ) = (- 9, -2)

The slope = m = 1

Now, The slope is calculated in points form

So, Slope = $\dfrac{y_2-y_1}{x_2-x_1}$

I.e m = $\dfrac{y_2-y_1}{x_2-x_1}$

or, 1 = $\dfrac{- 2 - y}{- 9- (-3)}$

or, 1 = $\dfrac{- 2 - y}{- 6}$

or, 1 × (-6) = - 2 - y

or, - 6 = - 2- y

or, y = - 2 + 6

∴ y = 4

So, The new points as

( $x_1$ , $y_1$ ) = (- 3, 4 )

( $x_2$ , $y_2$ ) = (- 9, -2)

So, the equation of line in slope - point form can be written as

y - $y_1$ = m ( x - $x_1$ )

i.e y - 4 = ( 1 ) × ( x - (-3) )

or, y - 4 = x + 3

∴ y = x + 3 + 4

Or, y = x + 7

So, The equation of line is y = x + 7

Hence The value of y is 4

And The equation of line is y = x + 7 . Answer

8 0

3 years ago