In this triangle, angles j and k are the same size. To find the size of angle j, we need to determine the measure of angle k. Unfortunately, the measure of angle k is not provided in the question. Therefore, we cannot determine the exact size of angle j without additional information.
However, if we assume that angle k is indeed 34°, as indicated in the diagram, then angle j would also be 34° since they are stated to be the same size. So, if angle k is 34°, then angle j would also be 34°. But please keep in mind that this assumption is based on the information given in the question, and we cannot confirm its accuracy without further details.