is this a linear equation

An equation of the form ax + by + c = 0 is said to be a linear equation if both a and b are not equal to zero. This means that ax + by + c = 0 is said to be a linear equation if any of this is true

(i)                  a  0, b = 0

(ii)                a = 0, b  0

(iii)               a  0, b  0

 

In the equation; 7x + 0y + 5 = 0, a = 7 which is not equal to zero, b is zero and c = 5.

This equation satisfies condition (i).

So, this equation is a linear equation.