b= 8
Step-by-step explanation:
If we rewrite the 2nd equation, it becomes
15y = -6x - 11 ---> y = (-2/5)x - (11/15)
In order for this system of equations to have no solution, they must have the same slope, i.e., they're parallel to each other. So rewriting the 1st equation,
20y = -bx + 11
---> -b/20 = -0.4 or b = 8
