Math I NEED checked, plz help?

Question

Okay i have to have these checked can you help me out?
x+y=5
x-y=9

3x=6
y-2x=-8

is (-4,16) the solution on this system of equations
y=8-2x
y=12+x


is (5,0) the solution
3x+y=15
2y-2.5=-0.5x



Admission fee is $1.50 for children and $4.00 for adults. 2,200 people enter the fair. $5050 is collected

write an equation showing the total number of people at the fair

write an equation showing the total cost the fair collected

Answer 1

is (-4,16) the solution on this system of equations
No.
16 = 8 - 2(- 4)
but
16 ≠ 12 - 4

is (5,0) the solution
3*5 + 0 = 15
2*0 - 2.5 = - 0.5*5
Yes