$9 is discounted from the regular price. If you find the discounted price you get $21. Then subtract the 21 from 30 and you get 9
If you are moving the center of circle 2 to the the center of circle 1, then the translation rule is (x,y) ---> (x+4, y+10).
Note how x = 1 turns into x = 5. So we add 4
Also, y = -2 turns into y = 8. We add 10
The scale factor to turn the radius r = 4 into r = 8 is 2. Basically we double the radius. We can divide the two radii to see 8/4 = 2
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Summary:
To go from circle 2 to circle 1, we apply these two transformations
translation: (x,y) ---> (x+4, y+10)
dilation: scale factor 2
note:
if you want to go backwards, go from circle 1 to circle 2, then undo the transformations above
Answer: 
<u>Step-by-step explanation:</u>
Since you are looking for the distance from home plate to second base, you are actually looking for the length of the diagonal of the square. Use the Pythagorean Theorem: a² + b² = c² where a and b are the side lengths and c is the length of the diagonal.
We can factor <span>4x^2-25 into (2x +5) * (2x -5) and
dividing by (2x -5)
yields (2x +5)
That neatened up pretty nicely.</span>
