Answer:
-8
Step-by-step explanation:
(x-3y=136) + (18x+3y=288) We collect both processes to make y's disappear
19x=-152
x=-8
No because there are 20 multiplied by 3 is 60. So the answer would be 60+144=204x12=2448 but the last answer was still correct
With cross multiplication you can find that they are the same. In both equations, x would be 100.
Children = .65 * people
people = 520 / .65
800 people were in attendance
