The Multiplication Property of Zero.
It states "the product of any number and zero is zero". Even if there are more than one multiplier - it is still 0.
So 5 x 0 = 0
100 x 0 = 0
41 x 0 x 3 = 0
etc.
Step-by-step explanation:

9y - 5x = 20
or, (9y - 5x) / 20 = 1
or, 9/20 y - 1/4 x = 1
compare with x/a + y/b = 1
you'll get
x intercept (a) = -4
y intercept (b) = 20/9
1 and one - twelfth
because 12gies 3 times in 37