Some studies show that high school students are more successful when the school day begins after 9 am. To test this theory,
Lake High School changes its school day start time from 7 am to 9 am. Which of the following methods would best describe
the study above?
O A experimental study
OB. observational study
OC. survey
OD
controlled experiment
a
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Answer:

do it got a picture

Step-by-step explanation:

Answer:

The value of T₂₀ - T₁₅ is -20.

Step-by-step explanation:

Given :

To Find :

Using Formula :

General term of an A.P.

[tex]\star{\small{\underline{\boxed{\sf{\red{ T_n = a + (n - 1)d}}}}}}[/tex]

Solution :

Firstly finding the A.P of T₂₀ by substituting the values in the formula :

[tex]{\dashrightarrow{\pmb{\sf{ T_n = a + (n - 1)d}}}}[/tex]

[tex]{\dashrightarrow{\sf{ T_{20} = a + (20 - 1) d}}}[/tex]

[tex]{\dashrightarrow{\sf{ T_{20} = a + (19)d}}}[/tex]

[tex]{\dashrightarrow{\sf{ T_{20} = a + 19 \times d}}}[/tex]

[tex]{\dashrightarrow{\sf{ T_{20} = a + 19d}}}[/tex]

[tex]{\star \: {\underline{\boxed{\sf{\pink{ T_{20} = a + 19d}}}}}}[/tex]

Hence, the value of T₂₀ is a + 19d.

[tex] \rule{190}1[/tex]

Secondly, finding the A.P of T₁₅ by substituting the values in the formula :

[tex]{\dashrightarrow{\pmb{\sf{ T_n = a + (n - 1)d}}}}[/tex]

[tex]{\dashrightarrow{\sf{ T_{15}= a + (15 - 1) d}}}[/tex]

[tex]{\dashrightarrow{\sf{ T_{15}= a + (14) d}}}[/tex]

[tex]{\dashrightarrow{\sf{ T_{15}= a + 14 \times d}}}[/tex]

[tex]{\dashrightarrow{\sf{ T_{15}= a + 14d}}}[/tex]

[tex]{\star{\underline{\boxed{\sf \pink{ T_{15}= a + 14d}}}}}[/tex]

Hence, the value of T₁₅ is a + 14d

[tex] \rule{190}1[/tex]

Now, finding the difference between T₂₀ - T₁₅ :

[tex]{\dashrightarrow{\pmb{\sf{T_{20} - T_{15}}}}}[/tex]

[tex]{\dashrightarrow{\sf{(a + 19d) - (a + 14d)}}}[/tex]

[tex]{\dashrightarrow{\sf{a + 19d - a - 14d}}}[/tex]

[tex]{\dashrightarrow{\sf{a - a + 19d - 14d}}}[/tex]

[tex]{\dashrightarrow{\sf{0+ 19d - 14d}}}[/tex]

[tex]{\dashrightarrow{\sf{19d - 14d}}}[/tex]

[tex]{\dashrightarrow{\sf{5 \times - 4}}}[/tex]

[tex]{\dashrightarrow{\sf{ - 20}}}[/tex]

[tex]{\star \: \underline{\boxed{\sf{\pink{T_{20} - T_{15} = - 20}}}}}[/tex]

Hence, the value of T₂₀ - T₁₅ is -20.

[tex]\underline{\rule{220pt}{3.5pt}}[/tex]

Step-by-step explanation:

Plot the point.

-1+3=2 and -2-5=-7

this is your new plot, (2,-7)

move the dot an equal distance across the x-axis, which is up and down.

Answer:

15

Step-by-step explanation:

The median is the "middle" number between a range of numbers. In this question, 15 is the median because is the number that is between the minimum number (5) and the maximum number (19) Hope this helps :)

Answer:

$10

Step-by-step explanation:

Compound probabilities that required AND use multiplication

The probability of compound events is of two types

As a general rule, the AND probability require products

Take for instance

P(A and B) = P(A) and P(B)

This gives

P(A and B) = P(A) *  P(B)

So, compound probabilities that required AND use multiplication

Read more about compound probabilities at:

https://brainly.com/question/1553768

#SPJ1

Answer:

w>-3

Step-by-step explanation:

Step-by-step explanation:

System of Linear Equations entered :

[1] 2x-y=4 [2] y-x=4

Equations Simplified or Rearranged :

  [1] 2x - y = 4   [2] -x + y = 4

Graphic Representation of the Equations :

y + 2x = 4 y - x = 4

Solve by Substitution :

// Solve equation [2] for the variable  y 

[2] y = x + 4

// Plug this in for variable  y  in equation [1]

  [1] 2x - (x +4) = 4   [1] x = 8

// Solve equation [1] for the variable  x 

  [1] x = 8 

// By now we know this much :

  x = 8   y = x+4

// Use the  x  value to solve for  y 

  y = (8)+4 = 12 

Solution :

 {x,y} = {8,12} 

Answer:

0

Step-by-step explanation:

........

Answer:

g=-10

Step-by-step explanation:

-g+2(3+g) = -4

-g+6+2g=-4

g=-4-6

g=-10

Answer:

2- × 5

Step-by-step explanation:

Answer:

85.5

Step-by-step explanation:

Answer:

(2*2 3+2) * (4*2 3-1/2)

(4*5) * (8*3-0.5) = (8*2.5)

20*200

4000

Answer: x = 1

Step-by-step explanation:

Answer:

(2^102•5^102)

Step-by-step explanation:

(10)^102 = (2•5)^102 = 2^102 • 5^102

Answer:

2. Write an equation of the parabola with vertex (3, 1) and focus

(3, 5o3

The total amount of revenue on the 23rd day is 322.65

Given the following parameters:

The revenue will be exprssed as:

r(d) = s(d) - p(d)

r(d) = 0.15d² – 4d + 80 - (15d + 45)

r(d) = 0.15d² – 19d + 35

Hence a function R(d) to model the total daily  revenue is r(d) = 0.15d² – 19d + 35

To get the total amount of revenue on the 23rd day, you will substitute t = 23 into the function

r(d) = 0.15d² – 19d + 35

r(23) =  0.15(23)² – 19(23) + 35

r(23) = 79.35 - 437 + 35

r(23) = -322.65

Hence the total amount of revenue on the 23rd day is 322.65

Learn more on function here: https://brainly.com/question/14307385

Answer:

For 8 b, draw 36 squares and for 8 c, it would be 144:)

Replacing x by 4 and y by 2, it is found that the value of the expression is of 8.

The expression given is:

[tex]x(x - y) - y(y^2 - x)[/tex]

We want to evaluate it for x=4 and y=2, hence, we replace x by 4 and y by 2, then:

[tex]4(4 - 2) - 2(2^2 - 4) = 4(2) - 2(0) = 8[/tex]

The value of the expression is of 8.

A similar problem, in which the objective is finding the value of an expression, is given at https://brainly.com/question/19548262

Answer:

B is the answer

Step-by-step explanation:

Answer:

E

Step-by-step explanation:

Hope this helped

Answer:

x = 90 degrees

y = 50 degrees

Step-by-step explanation:

The angle where x lies is a right angle, and right angles = 90 degrees. A triangle adds up to 180 degrees, so you add 90 and 40 together and then subtract that from 180 degrees.

Answer:

I can't see much so take one more than I can help

Answer: Sunday

Step-by-step explanation:

The 27th would be tuesday

The 3rd would be tuesday

The 10th would be tuesday

The 15th would be sunday

Answer:

3 people.

Step-by-step explanation:

493÷7=70 with 3 remaining.

Answer:

a) 45 minutes

b) 2 miles

c) 8 miles per hour

d) 7.5 minutes per mile

Step-by-step explanation:

a) (150/20) x 6 = 45 minutes

b) (20/150)(15) = 2 miles

c) (20/150)(60) = 8 miles per hour

d) 150/20 = 7.5 minutes per mile

20 miles in 150 minutes = 20/150 miles per minute = 2/15 miles per minute

distance/speed = time

6 miles / (2/15) miles per minute = 45 -> 45 minutes

time*speed=distance

15 minutes * 2/15 miles per minute = 2 miles

Her speed, 2/15 is in miles per minute. To convert to miles per hour, you multiply by 60 (60 minutes in an hour). 2/15*60=8 miles per hour

minutes per mile = 150 minutes for 20 miles = 150/20=15/2 minutes per mile

15/2=7.5

7.5 minutes per mile

Answer:

20 buses

Step-by-step explanation:

Using the given ratio, we can see that for every 12 taxis, there are 5 buses and 18 bikes.

To get from 18 bikes to 72 bikes, we multiply by 4. Therefore, to figure out the number of buses, we multiply it by 4.

5 * 4 = 20

Hope this helps! :D

Answer: The Y intercept is 128 as well, which is the original velocity. Technically it should be v - intercept but whatever. The y  / v intercept is the original velocity. The X intercept should be the t intercept but again whatever. The x/t intercept is 4, meaning that the velocity is zero when t is 4

Step-by-step explanation: y/v intercept is when t = 0. v = 128 - 32(0) = 128

It is the initial velocity at t = 0. The X/t intercept is when v = 0. 0 = 128 - 32t, so 32t = 128, so t = 4. The x intercept means when the velocity is zero, which means that the ball is at its highest/farthest point.

Answer: No!

Step-by-step explanation: This is a parabola. The graph for this function is not straight. We can also tell this is not a linear function because the degree of the function is 2.

Hope this helps :)

No.

y = 3x² + 2 has a degree of 2. So, it'll not make a graph which is a straight line. It's NOT a linear function. Linear functions have a degree of 1 or 0.

This is a quadratic polynomial (degree = 2) & when drawn on a graph, it'll make a parabola.

_____

Hope it helps ⚜