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Some experimentation was required

Because I didn't know the diameter of the beachball, I had to experiment to determine how far to move it to the left of the origin to locate it at the leftside of the Stage as shown in Image 4 . I settled on a value of -200 for the x coordinate and a value of 0 for the y coordinate.

Positioning the other beachball

In the interest of brevity, I won't show the code required to position the beachball on the right side of the Stage. I did exactly the same thing for that beachballexcept that I specified the value of the x coordinate to be 200 instead of - 200. This causes the beachball named RightBeachball to move to the right side of the Stage when the user clicks the green flag.

The basketball

Initializing the position of the basketball

Image 7 shows a portion of the rightmost panel after clicking on the sprite named Basketball . (Note the image of the basketball in the upper right corner. When this is an image of the basketball, all of the scripts in the rightmost panel apply to thebasketball sprite.)

Image 7. initializing the position and orientation of the basketball.

Missing image.
Image 7. Initializing the position and orientation of the basketball.

You will note that the tan block and the uppermost blue block in Image 7 arethe same as in Image 6 except that the x coordinate value is set to 0. This causes the basketball to move to the origin when the user clicks the greenflag.

Initializing the orientation of the basketball

However, Image 7 contains a block that is not contained in Image 6 . The bottom blue block in Image 7 is used to set the orientation of the basketball. (By orientation, I mean the direction that the basketball is facing.)

It may seem strange to say that a round basketball is facing in one direction or the other. However, every sprite has a front, back, top, and bottomeven in those cases where it is not visually obvious. The orientation would be visually obvious if I were to use an animal for the sprite in place ofthe basketball. You can tell which direction the basketball is facing by observing the curved diagonal lines on the basketball.

After you drag the blue block labeled point in direction into the rightmost panel, you can click the arrow in the white box to expose the followingfour choices:

  • (90) right
  • (-90) left
  • (0) up
  • (180) down

As you can see, I selected the choice that causes the basketball to face to the right. As a result, when the user clicks the green flag, the basketballwill move to the origin and turn to face the right.

Handling mouse events on the basketball

Image 8 shows all of the code in the rightmost panel that applies to the basketball.

Image 8. all of the code that applies to the basketball.

Missing image.
Image 8. All of the code that applies to the basketball.

The top script in Image 8 is another copy of the script that was shown in Image 7 . At this point, we are interested in the behavior of the bottom script in Image 8 .

Behavior of the bottom script

The dark tan block labeled when this sprite clicked specifies that all of the actions produced by the blocks attached to that block will occur when the userclicks the basketball with the mouse. Furthermore, those actions will occur in top-to-bottom order.

Questions & Answers

how did you get 1640
Noor Reply
If auger is pair are the roots of equation x2+5x-3=0
Peter Reply
Wayne and Dennis like to ride the bike path from Riverside Park to the beach. Dennis’s speed is seven miles per hour faster than Wayne’s speed, so it takes Wayne 2 hours to ride to the beach while it takes Dennis 1.5 hours for the ride. Find the speed of both bikers.
MATTHEW Reply
420
Sharon
from theory: distance [miles] = speed [mph] × time [hours] info #1 speed_Dennis × 1.5 = speed_Wayne × 2 => speed_Wayne = 0.75 × speed_Dennis (i) info #2 speed_Dennis = speed_Wayne + 7 [mph] (ii) use (i) in (ii) => [...] speed_Dennis = 28 mph speed_Wayne = 21 mph
George
Let W be Wayne's speed in miles per hour and D be Dennis's speed in miles per hour. We know that W + 7 = D and W * 2 = D * 1.5. Substituting the first equation into the second: W * 2 = (W + 7) * 1.5 W * 2 = W * 1.5 + 7 * 1.5 0.5 * W = 7 * 1.5 W = 7 * 3 or 21 W is 21 D = W + 7 D = 21 + 7 D = 28
Salma
Devon is 32 32​​ years older than his son, Milan. The sum of both their ages is 54 54​. Using the variables d d​ and m m​ to represent the ages of Devon and Milan, respectively, write a system of equations to describe this situation. Enter the equations below, separated by a comma.
Aaron Reply
find product (-6m+6) ( 3m²+4m-3)
SIMRAN Reply
-42m²+60m-18
Salma
what is the solution
bill
how did you arrive at this answer?
bill
-24m+3+3mÁ^2
Susan
i really want to learn
Amira
I only got 42 the rest i don't know how to solve it. Please i need help from anyone to help me improve my solving mathematics please
Amira
Hw did u arrive to this answer.
Aphelele
hi
Bajemah
-6m(3mA²+4m-3)+6(3mA²+4m-3) =-18m²A²-24m²+18m+18mA²+24m-18 Rearrange like items -18m²A²-24m²+42m+18A²-18
Salma
complete the table of valuesfor each given equatio then graph. 1.x+2y=3
Jovelyn Reply
x=3-2y
Salma
y=x+3/2
Salma
Hi
Enock
given that (7x-5):(2+4x)=8:7find the value of x
Nandala
3x-12y=18
Kelvin
please why isn't that the 0is in ten thousand place
Grace Reply
please why is it that the 0is in the place of ten thousand
Grace
Send the example to me here and let me see
Stephen
A meditation garden is in the shape of a right triangle, with one leg 7 feet. The length of the hypotenuse is one more than the length of one of the other legs. Find the lengths of the hypotenuse and the other leg
Marry Reply
how far
Abubakar
cool u
Enock
state in which quadrant or on which axis each of the following angles given measure. in standard position would lie 89°
Abegail Reply
hello
BenJay
hi
Method
I am eliacin, I need your help in maths
Rood
how can I help
Sir
hmm can we speak here?
Amoon
however, may I ask you some questions about Algarba?
Amoon
hi
Enock
what the last part of the problem mean?
Roger
The Jones family took a 15 mile canoe ride down the Indian River in three hours. After lunch, the return trip back up the river took five hours. Find the rate, in mph, of the canoe in still water and the rate of the current.
cameron Reply
Shakir works at a computer store. His weekly pay will be either a fixed amount, $925, or $500 plus 12% of his total sales. How much should his total sales be for his variable pay option to exceed the fixed amount of $925.
mahnoor Reply
I'm guessing, but it's somewhere around $4335.00 I think
Lewis
12% of sales will need to exceed 925 - 500, or 425 to exceed fixed amount option. What amount of sales does that equal? 425 ÷ (12÷100) = 3541.67. So the answer is sales greater than 3541.67. Check: Sales = 3542 Commission 12%=425.04 Pay = 500 + 425.04 = 925.04. 925.04 > 925.00
Munster
difference between rational and irrational numbers
Arundhati Reply
When traveling to Great Britain, Bethany exchanged $602 US dollars into £515 British pounds. How many pounds did she receive for each US dollar?
Jakoiya Reply
how to reduced echelon form
Solomon Reply
Jazmine trained for 3 hours on Saturday. She ran 8 miles and then biked 24 miles. Her biking speed is 4 mph faster than her running speed. What is her running speed?
Zack Reply
d=r×t the equation would be 8/r+24/r+4=3 worked out
Sheirtina
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Source:  OpenStax, Teaching beginners to code. OpenStax CNX. May 27, 2013 Download for free at http://cnx.org/content/col11498/1.20
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