Answer:
17.5
Step-by-step explanation:
The distance between two points is the root of the sum of the squares of the horizontal and vertical distances. Those are fairly easily read from a graph. So, we have ...
JK = √(3^2+2^2) = √13
KL = √(5^2+3^2) = √34
LJ = √(8^2+1^1) = √65
The perimeter is the sum of these, so is ...
P = √13 +√34 +√65 ≈ 17.4988 ≈ 17.5
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In the attached graph, the number "c" is the sum of "a" and "b". The number "a" is the total length of the two longest sides of the triangle, and "b" is the length of the shortest side. You will note that c=17.5.