- What is -7- (-4)? Explain how you know.​

By applying the law of reflection to the ray of sunlight, the value of x is equal to 5.

The law of reflection is a theorem which states that the magnitude of the angle of incidence is equal to the magnitude of the angle of reflection when a ray of light is reflected off a surface such as a plane mirror.

Mathematically, law of reflection can be represented or modelled by this mathematical expression:

sinθi = sinθr

Where:

By applying the law of reflection to the ray of sunlight (see attachment), we have the following equation:

(3x - 10)° = (2x + 5)°

3x + 2x = 10 + 5

5x = 15

x = 15/3

x = 5.

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Proportionately, if there are 6 blue beads in the bag, and blue beards are 6 or 2/9 of the total beads, the number of purple beads in the bag is 21.

Proportion refers to the numerical ratio of a value to another.

Proportion shows the quantity of a value contained in another variable.

Since proportions are fractional values, like ratios, they are represented using decimals, fractions, and percentages.

The ratio of blue beards to purple beads = 2:7 or 2/9

The number of blue beads in the bag = 6

The total number of beads in the bag = 27 (6/2 x 9)

The number of purple beads in the bag = 21 (27 x 7/9)

Thus, based on the given proportional ratio of the blue beads to the purple beads, there are 21 purple beads in the bag.

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Exponential decay formula:

y is the number of tickets sold at t years

a is the initial number of tickets sold

r is the rate of drop (in decimal form)

t is the time in years

8 years from now:

The three equations that will emerge from the given matrix will be:

So, the equations for the given matrix will be:

[0. 2. 3. / 4]

[8 -1 -2  / 5 |

[2. 0. 1  / 9 ​]

Now, the equation will be:

Therefore, the three equations that will emerge from the given matrix will be:

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The slope of the line through the points (6,5) and (4, 10) exists -5/2.

A line's slope in mathematics is defined as the ratio of the change in the y coordinate to the change in the x coordinate. Both the net change in the y-coordinate and the net change in the x-coordinate are denoted by Δy and Δx, respectively. where "m" represents a line's slope. So, the slope of a line is tan.

Determine the coordinates of two points along the line that you choose. Find the difference between these two points' y-coordinates (rise). Find the difference between these two points' x-coordinates (run). Divide the difference in x-coordinates (rise/run or slope) by the difference in y-coordinates.

Let the two points are (6, 5) and (4, 10)

(x1, y1) = (6, 5) and (x2, y2) = (4, 10)

The equation of slope of the line through the points (x1, y1) and (x2, y2) = y2 - y1 / x2 - x1

substitute the values in the above equation, and we get

= 10 - 5 / 4 - 6

= 5 / -2

Therefore, the slope of the line through the points (6,5) and (4, 10) exists -5/2.

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In order to calculate the total spending in the town each year, first, multiply by the 70% that is spent within the town,

Also, multiply by 70% of the amount people will spend after they receive it in town,

Answer:

The total spending in the town each year is $1,960,000

SOLUTION

We want to find which of the following values make the inequality

x ≤ 16.3 to be true.

This inequality means that x is equal to 16.3 or less than 16.3. So the numbers that fall under this are numbers smaller than 16.3 and also 16.3.

The numbers that fall under here are 8, 1/4, -3 and 16.3

Hence the answer b, c, e and f

The standard deviation is a statistic that expresses how much variance or dispersion there is in a group of numbers. While a high standard deviation suggests that the values are dispersed throughout a wider range, a low standard deviation suggests that the values tend to be close to the established mean.

How to calculate the probability distribution's mean: Steps

A specific genetic mutation affects 4% of the population. 300 persons are chosen at random. Find the standard deviation for the proportion of the 300 groups who have the genetic mutation.

Standard deviation is calculated as follows: 0.04 * 0.93/300 * sqrt(p*(1-p)/n) (0.000124).

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To simplify a phrase, create an equivalent expression without any terms that are identical.The expression will then be rewritten using the fewest terms feasible.

What is an equation to simplify?

      2+1

    =   3

    2³  = 8

    first one 8

   2.  x²× x°

   = x ²+°

   3.a6_a4

  = a2

 4.   x×x×y×y

   =x²y²

  5 x²×x×y×y²

 =   x³y³

  6.(mn)5

=  m5N5

 7 (abc)²

 = a²b²c²

 8.(p²q)³

 p6q3

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Based on the temperature at 6:00 am and the temperature at 6:00pm, the change in temperature can be shown by the formula D. |–5 – 7| = |–12| = 12°F.

To find the change in temperature, you need to subtract the temperature at 6: 00 pm from the temperature at 6: 00 am.

The change in temperature is therefore:

= | temperature at 6 am - temperature at 6pm |

= | -5 - 7 |

= | - 12 °F|

The absolute value of - 12 °F is 12 °F which was therefore the change in temperature.

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The expression that represents the perimeter and area of the rectangle are 10x + 4 and 6x²- 24.

The rectangle is a quadrilateral with opposite sides equal to each other.

Opposite sides of a rectangle is also parallel to each other.

Therefore,

perimeter of a rectangle = 2(l + w)

where

Therefore,

l = 3x + 6

w = 2x - 4

Hence,

perimeter of a rectangle = 2(3x + 6 + 2x - 4)

perimeter of a rectangle = 2(5x + 2)

perimeter of a rectangle = 10x + 4

Let's find the expression that represent the area of the rectangle.

Hence,

area of a rectangle = lw

area of a rectangle = (3x + 6)(2x - 4)

area of a rectangle = 6x² - 12x + 12x - 24

Therefore,

area of a rectangle = 6x²- 24

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Given:

Initially, the cell phone was 80% charged.

Then started to lose 8% charge for each hour thereafter.

To find:

The equation for B in terms t

Answer:

[tex]\displaystyle y = \frac{-2}{7}[/tex]

Step-by-step explanation:

   To solve, we will isolate the variable.

   Given:

-12/7 = 6y

   Divide:

[tex]\displaystyle \frac{\frac{-12}{7} }{6} =\frac{6y}{6}[/tex]

   Simplify the right side:

[tex]\displaystyle \frac{\frac{-12}{7} }{6} =y[/tex]

   "Keep, change, flip" on the left side:

[tex]\displaystyle \frac{-12}{7} *\frac{1}{6} = y[/tex]

   Multiply:

[tex]\displaystyle \frac{-12*1}{7*6}= y[/tex]

[tex]\displaystyle \frac{-12}{42}= y[/tex]

   Simplify and reflexive property:

[tex]\displaystyle y = \frac{-2}{7}[/tex]

Normal time taken for operation = 7.7

Charlene's work performance is faster than normal time.

Need to define Charlene's average time:

8.4 + 8.6 + 8.3 + 8.5 + 8.7 + 8.5)/6

Avg time taken= 8.5.

Performance rating = 110/100 = 1.1

normal time taken:  8.5/1.1

normal time taken= 7.7

hence, 8.5 [tex]\geq[/tex] 7.7

Charlene is faster than normal time.

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the width of the wall is 21 3/8 = 171/8

the width of a tile is 4 1/2 = 9/2

so the number of tiles is

(171/8) / (9/2) = 171x2 / (9 x8) = 4.75

so the no of tiles needed is 5.

Given (x+ c) is a common factor of (x^2- ax- b )and (2x^2+b)

x= -c is a root of x^2- ax- b= 0 and x^2+ b= 0

Concept used

Quadratic equation is an algebraic equation of the second degree in x. The quadratic equation in its standard form is ax2 + bx + c = 0, where a and b are the coefficients, x is the variable, and c is the constant term.

-b±√b²-4ac/2a

i) 1- 2a+b= 0

ii) 4+ b^b- 2a= 0

4- 2a+b=0,4+ b- 2a= 0

2a+b= 2c+d

2(c−a)= b−d

(c−a)/ (b−d)​= 2

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We know that specific products multiply specific kinds of binomials, so these binomials will be the product's factors.

Example:

So, we know that special products are multiplying special types of binomials which means that these binomials will be the factors of the product.

For example:

Therefore, we know that specific products multiply specific kinds of binomials, so these binomials will be the product's factors.

Example:

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Answer: The slope is -0.7, the rise is -1.4, and the run is 2

We have the monthly cost is fixed: $29.95.

The cost varies directly as the number of minutes since the total cost per month will be:

If we make a call and spend 30 minutes. We need to add this cost to the payment:

Take into account that the slope of a line is given by the following formula:

where (x1,y1) and (x2,y2) are two points on the line.

In this case:

(x1,y1) = (p,3)

(x2,y2) = (6,p)

By replacing the previous values into the formula for m, we get:

Now, by making m = 2 and solving for p, we obtain:

Hence, the value of p is p = 5

Hello, in this question we will use the "Sinus Theorem".

The general formula of the Sine Theorem is as follows;

We are given the length of the two sides and the sine value of the angle of the unknown side. We also know the area of the triangle. Let's substitute the required values in this formula to get the result.

In the last step, we are left with a quadratic equation with one unknown. To solve this equation, we need to calculate the discriminant value.

There are only two roots of a quadratic equation with one unknown.

Thus our x values;

We cannot accept the first root [tex]x_1[/tex]. Because length cannot be a negative value.

Ans = [tex]x_{2}=\frac{-1+\sqrt{177} }{4}=3.076[/tex]

The given statement "Sal earns $480 per week. Lidia earns $300 per week. Are their salaries proportional if Sal works 40 hours per week and Lidia works 25 hours per week" is true.

As given in the question,

If one amount is proportional to another, the two amounts increase and decrease at the same rate so there is always the same relationship between them

a:b = c:d

a ÷b = c ÷d

ad = bc

let Sal earns $480 per week and he works 40hours per week

  480÷40 = 12

Lidia earn $300 per week and she works 25 hours per week

   300÷25 = 12

Cross product of their salaries is  

480×25=1200

300×40=1200

The ratio of their salaries and their product are equal.

Hence, The given statement "Sal earns $480 per week. Lidia earns $300 per week. Are their salaries proportional if Sal works 40 hours per week and Lidia works 25 hours per week" is true

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Time taken by the smaller hose to fill the pool on its own = 75 minutes

Time taken to fill the swimming pool by the larger hose and smaller hose working together = 30 minutes

Time taken by the larger hose to fill up the swimming pool = 50 minutes

Let 'x' be the time taken by the smaller hose to fill the swimming pool on its own.

In 30 minutes, the larger and smaller hoses together can fill the swimming pool. So in 1 minute, it can fill up 1/30 of the swimming pool.

In 50 minutes, the larger hose can fill up the swimming pool on its own. So the larger hose can fill up 1/50 of the pool in 1 minute.

It takes 'x' minutes for the smaller hose to fill up the pool on its own. So in 1 minute, the smaller hose alone can fill up 1/x of the pool.

Hence 1/30 = 1/x +1/50

⇒ 1/30 = (50+x)/50x

⇒ 30 = 50x/(50+x)

⇒ 30 (50 + x) = 50x

⇒ 1500 + 30x = 50x

⇒ 20x = 1500

⇒ x = 1500/20

⇒ x = 75 minutes.

Thus the smaller hose alone takes 75 minutes to fill up the pool.

The question is incomplete. Find the complete question below:

Working together, it takes two different sized hoses 30 minutes to fill a small swimming pool. If it takes 50 minutes for the larger hose to fill the swimming pool by itself, how long will it take the smaller hose to fill the pool on its own?

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We have to indicate the steps to follow in order to evaluate:

(12.9-3.1) x 6.2-2 + 43

So FIRST: we solve for the operation indicated inside the parenthesis

12.9 - 3.1 = 9.8 (we subtract 3.1 from 12.9)

This is the answer you need to select.

SOLUTION

To get how many more stickers were shipped last month than this month, we simply subtract this month's shipment from last month's shipment.

This becomes

Therefore, the we have 1,000,000,000 to the nearest billion.

Option D is the correct answer

By solving inequality, we can conclude that the artist will not make a profit if he sells 15 necklaces.

So, is the artist in profit if he sells 15 necklaces:

Inequality is 12n ≥ 170 +3.50n: (let n = 15)

Therefore, by solving inequality, we can conclude that the artist will not make a profit if he sells 15 necklaces.

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The correct question is given below:
A jewelry artist is selling necklaces at an art fair. It costs $170 to rent a booth at the fair. The cost of materials for each necklace is $3.50. The artist is selling the necklaces at $12 each. The inequality 12n> 170 +3.50n represents the situation in which the artist makes a profit. Will the artist make a profit if he sells 15 necklaces? Show how you know.

Given data:

The given ratio is 9:27.

The given ratio can be written as,

Thus, the given ratio can be written as 1:3 so, second option is correct.

Answer: [tex]f^{-1}(x)=-\frac{1}{9}(x+10)[/tex]

Step-by-step explanation:

[tex]f(x)=-9x-10 \implies x=-9f^{-1}(x)-10\\\\x+10=-9f^{-1}(x)\\\\f^{-1}(x)=-\frac{1}{9}(x+10)[/tex]