The value of y varies directly with x and y 8 when x 2 find y when x 10 answer

Laboratory experiment shows that the life of the average butterfly is normally distributed with a mean of 18.8 days and a standa

inessss [21]

Answer:

a) 0.4164

Step-by-step explanation:

Mean lifespan (μ) = 18.8 days

Standard deviation (σ) = 2 days

For any given lifespan 'X', the z-score is:

$z=\frac{X- \mu}{\sigma} \\z=\frac{X- 18.8}{2}$

For X=12.04 days:

$z=\frac{12.04 - 18.8}{2} \\z=-3.38$

A z-score of -3.38 falls in the 0.036-th percentile of a normal distribution.

For X=18.38 days:

$z=\frac{18.38 - 18.8}{2} \\z=-0.21$

A z-score of -3.38 falls in the 41.68th percentile of a normal distribution.

The probability that a butterfly lives between 12.04 and 18.38 days is

$P=41.68-0.036\\P=41.64\%\ or\ 0.4164$

6 0

3 years ago

Find the axis of symmetry of the graph of the function. (5 points) f(x) = 3x2 + 12x + 9

Kryger [21]

Considering the definition of axis of symmetry, the axis of symmetry of the graph of the function f(x) = 3x²+ 12x+ 9 is x=-2.

<h3>Axis of symmetry</h3>

An axis of symmetry is an imaginary reference line that, when dividing any shape into two parts, its opposite points are equidistant from each other, that is, they are symmetrical.

In other words, the axis of symmetry is a vertical line that divides the parabola into two congruent halves.

The axis of symmetry is the line perpendicular to the "x" axis that contains the vertex of the function, that is, it always passes through the vertex of the parabola. So the x-coordinate of the vertex is the equation of the axis of symmetry.

That is, in a quadratic function that has the form:

f(x)= ax² + bx + c

the axis of symmetry is a vertical line and it is defined as $x=\frac{-b}{2a}$ .

<h3>Axis of symmetry of f(x) = 3x² + 12x + 9</h3>

In this case, you know:

a= 3
b=12
c=9

Replacing in the definition of axis of symmetry:

$x=\frac{-12}{2x3}$

Solving:

$x=\frac{-12}{6}$

x= -2

Finally, the axis of symmetry of the graph of the function f(x) = 3x²+ 12x+ 9 is x=-2.

Learn more about axis of symmetry:

brainly.com/question/24737967

brainly.com/question/10473291

#SPJ1

3 0

2 years ago

Describe the rotation of J

Serga [27]

Answer:

The coordinates of J' when rotating by 90° counterclockwise will be: J'(3, 1)

The coordinates of J' when rotating by 90° clockwise will be: J'(-3, -1)

Step-by-step explanation:

Square JKLM with vertices

J(1, -3)

K(5, 0)

L(8, -4)

M(4, -7)

We have to determine the answer for the image J' of the point (1, -3) when we rotate the point by 90° counterclockwise, we need to switch x and y, make y negative.

In other words, the rule to rotate a point by 90° counterclockwise.

P(x, y) → P'(-y, x)

As we are given that J(1, -3), so the coordinates of J' will be:

J(1, -3) → J'(3, 1)

Therefore, the coordinates of J' when rotating by 90° counterclockwise will be: J'(3, 1).

When the point is rotated by 90° clockwise, we need to switch x and y, make x negative.

In other words, the rule to rotate a point by 90° clockwise.

P(x, y) → P'(y, -x)

As we are given that J(1, -3), so the coordinates of J' will be:

J(1, -3) → J'(-3, -1)

Therefore, the coordinates of J' when rotating by 90° clockwise will be: J'(-3, -1)

3 0

3 years ago

Approximately 9 out of every 50 people who saw a movie this week say they watched it on Netflix. Suppose we want to find the pro

uysha [10]

Answer:

1. As a fraction: 9/50

2. As a proportion: x/1 = 9/50

3. As a percentage: 18%

Explanation:

1. As a fraction:

Depart from the definition of probability: probability is the number of favoragle outcomes divided by the total number of possible outcomes:

Probability = number of movie-goers who say they watched a movie on Netflix this week / number of movie-goers that saw a movie this week

Probability = 9 / 50

2. As a proportion:

A proportion is the equality of two ratios. In this case you must set the ratio of people who say they watched it on Netflx, x, per every people who saw a movie this week, 1, equal to the ration 9 /50.

Hence, the proportion that shows the probability is:

x / 1 = 9 / 50

Where x is the probability.

3. As a percentage

You just have to multiply the probability by 100:

(9/50) × 100 = 18%

6 0

3 years ago

15% of what number is equal to 9

just olya [345]

The percentage of 15% of 9 is 60% (I think)

8 0

2 years ago

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