Question

determine the value of and b for which the system of linear equations 2x+3y=7,2ax+(a+b)y=28,has infinite number of solutions

Answer 1

For infinite no of solutions a1/a2=b1/b2 not = c1/c2 => 2/a= 3/(a+b) not = 7/28 => 2a+2b=3a => a=2b ------------(1) and 2/a not = 1/4now a not = 8 and b not = 4