the total number of people including adults and children are 1200. given $7 for adults ($7×a = 7a) and $3 for children ($3×c = 3a) that would make it $6400 for the night
So the total number of movie tickets sold was 1200. This means that a + c = 1200 because a represents the number of adult tickets purchased and c represents the number of child tickets purchased. The total money they made off the movie was $6400. This means 7 multiplied by the number of adult tickets would result in the total they earned off adult tickets, and 3 multiplied by the number of child tickets would result in the total they earned off child tickets. This total equals 6400. So 7a + 3c = 6400. These are our two equations: a + c = 1200 and 7a + 3c = 6400. The answer choice that matches this is choice A, so your answer is A. Hope this helps. Feel free to ask more questions, or ask more questions about my explanation.
