3(6-a)=(5a/2)(4-b),18-3a=10a-5ab/2,13a-5ab/2=18,a(13-5b/2)=18a/3=(4-b)/b,ab=12-3b,a=(12-3b)/b((12-3b)/b)*(13-5b/2)=18(12-3b)*(26-5b)=36b15b^2-60b-78b+312=36b15b^2-174b+312=0b1=(174+(174^2-4*15*312)^0....