I need to but exactly 100 farm animals I have $100. sheep cost $0.50, cattel cost $1 and hourses cost $10. i must spend all of the $100 dollors pls explain.

Answer 1

H+C+S=100
S*.5+H*10+C*1=100

(100-H-C).5+10H+ C=100
9.50H+.5C=50
let H=5, then C=5
got back to the first equation, then
S=100-H-C= 90

There is not a "unique" solution, there are a multitude of solutions.

To get a unique solution with three unknowns,you need three equations.