10/3 is the answer
_______________
Answer:
Adults $ 17
Students: $8
Step-by-step explanation:
Adults: x
Students: y
a) 25x + 31y = 673
b) 27x +31y = 707
Elimination:
a) -1(25x + 31y = 673) = -25 -31y = -673
a + b
= (-25 -31y = -673) + (27x + 31y = 707)
= 2x = 34
x = 34/2
x = 17
Substitution a or b:
a) 25(17) + 31y = 673
425 + 31y = 673
31y = 673 - 425
31y = 248
y = 248/31
y = 8
An equation has infinitely many solutions if it can be manipulated all the way to an identity (i.e. an equality where the right and left hand side are the same). We have:
A) 
which is impossible
B) 
which is an equality
C) 
which has a unique solution
D) 
which has a unique solution