Final answer:
Without additional information on the dimensions of the triangle or vectors, we cannot determine the length of Po in isosceles triangle APQR. The reference to vectors and proper length Lo implies methods for calculating lengths in vector diagrams, not standard geometry.
Step-by-step explanation:
To find the length of Po in an isosceles triangle with vertex O and base APQR, we need more information about the dimensions of the triangle or the specific relationship between Po and the other sides. However, based on the information provided related to vectors and triangles, we can infer that in scenarios involving vector addition and vector subtraction, the diagonals of a parallelogram represent the sum and difference of vectors, respectively. If Po were a diagonal in such a context, we could use the Pythagorean theorem or trigonometric relationships to find its length given the other sides of the right triangle.
But without specific dimensions or a clear context for the isosceles triangle APQR and line segment Po, we cannot provide a numerical answer. If Po is supposed to represent a vector in a parallelogram formed by vectors A and B, as mentioned in the reference information, we would need the lengths of A and B or the angles involved to calculate Po using the proper length Lo method.