At 4 months the cost for each gym $250
the key is to write
as
which can be easily seen as an area of a rectangle with one side length n and the other (n+1). That explains the rectangle made of dots - 3 x 4
Now you only have half of them because of the 1/2. So that explains the lower "triangle" of dots being greyed out - they do not count in the area (upper triangle). So the count of the dark dots corresponds to the original expression.
For n=5 you can draw a similar rectangular matrix with 5 x 6 dots. And count only the upper triangular part.
Answer:
20 floor
Step-by-step explanation:
16 - 11 = 5 5 + 15 = 20
The elevator is on the 20th floor
<span>x^2 + y^2 + 8x – 6y + 21 = 0
x^2 + 8x +16 + y^2 -6y +9 = -21 + 16 +9
(x+4)^2 + (y-3)^2 = 4
So the radius is 2
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