On HW3, I couldn't find the eqm. points besides (0,0) and (77,95) in the predator prey problem - what are they and how do we find them?

Shreesh P. Mysore, Oct 28 02

Denote the right hand sides of the equation by f1(x1,x2) and f2(x1,x2) respectively. (x1,x2) in R2 is an eqm point if f1(x1,x2)=0 and f2(x1,x2)=0.
(1) f1(x1,x2)=0 => x1=0 or ax2+bx1=br.
(2) f2(x1,x2)=0 => x2=0 or ax1-bx2=df.
Since we want both (1) and (2) to be satisfied, this can happen in any one of 4 ways (each condition from (1) can be paired with any one of 2 conditions from (2)). Therefore the four possible solutions are
(a) x1=0 and x2=0 (or)
(b) x1=0 and ax1-bx2=df (or)
(c) ax2+bx1=br and x2=0 (or)
(d) ax2+bx1=br and ax1-bx2=df
You found solutions (a) and (d).