Question: who was the first english mathematician who used the modern symbol of equality in 1557
[{'answer': 'Robert Recorde', 'provenance': [{'wikipedia_id': '310247', 'title': 'Robert Recorde', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 14, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '310247', 'title': 'Robert Recorde', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 181, 'bleu_score': 0.710066144478382, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10045408896388487761}, 'section': 'Section::::Abstract.'}]}]