Respuesta :
The answer is 9 because the distance formula is square root of (x2-x1)^2 + (y2-y2)^2
Answer: The length of side DE is 9 units.
Step-by-step explanation: Given that the co-ordinates of the end-points of DE are D(0, 3) and E(0, 12).
We are to find the length RT of the polygon.
We know that
the length of a line segment with endpoints P(a, b) and Q(c, d) is equal to the distance between the points P and Q.
By distance formula, the distance between P(a, b) and Q(c, d) is
[tex]D=\sqrt{(c-a)^2+(d-b)^2}.[/tex]
So, the distance between D(0, 3) and E(0, 12) is given by
[tex]DE=\sqrt{(0-0)^2+(12-3)^2}=\sqrt{9^2}=9.[/tex]
Thus, the required length of DE is 9 units.
