Indefinitely many
The lines are on each other so every solution is correct
Answer:

Step-by-step explanation:
In this question, you would solve for "a".
Solve:
K = 4a + 9ab
Since we have our "a" on the same side, we can factor it out from the variables:
K = a(9b + 4)
To get "a" by itself, we would have to divide both sides by 9b + 4:
K/9b+ 4 = a
Your answer would be K/9b+ 4 = a
It would look like this: 
'is' means equals
'of' means mutily so
we have
18 =0.4 times what
divide both sides by 0.4
45=what
the answer is the number is 45