The distance between x_1 and x_2 is computed by line-length(x1, x2). The distance between y_1 and y_2 is computed by line-length(y1, y2). Below is the equation to compute the hypotenuse of a right triangle with those amount for legs:
√( line\mbox-length(x_2, x_1)^2 + line\mbox-length(y_2, y_1)^2 )
Suppose your player is at (0, 2) and a character is at (4, 5). What is the distance between them?
1. Identify the values of x_1, y_1, x_2, and y_2
| x_1 | y_1 | x_2 | y_2 |
|---|---|---|---|
(x-value of 1st point) |
(y-value of 1st point) |
(x-value of 2nd point) |
(y-value of 2nd point) |
|
The equation to compute the distance between these points is:
√( line\mbox-length(4, 0)^2 + line\mbox-length(5, 2)^2 )
2. Translate the expression above, for (0,2) and (4,5) into a Circle of Evaluation below.
Hint: In our programming language num-sqr is used for x^2 and num-sqrt is used for √x
3. Convert the Circle of Evaluation to Code below.
These materials were developed partly through support of the National Science Foundation,
(awards 1042210, 1535276, 1648684, and 1738598). 
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