ASAP! If you have 25,100 dollars how much more to get to 100,000 dollars!?

Galen sold tickets of his church’s carnival for a total of $2,820. children’s tickets cost $3 each and adult tickets cost $5 each. the number of children’s tickets sold was 30 more than 3 times the number of adult tickets slod. how many children’s ticket and how many adult tickets did he sell?

14. (05.02 lc) what is the value of y in the solution to the following system of equations? (5 points) 2x + y = −4 5x + 3y = −6

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?