No a linear equation are not the same as a linear function. The linear function is written as Ax+By=C. The linear equation is f{x}=m+b.

An equation is linear if the highest power of the unknown in the equation is 1

for example an equation with just a variable to the power one such as x, y and so on is linear but one with x2, y2 and above is not linear

Y = 5X - 3

It form a linear function; a line.

A linear equation can have only one zero and that is the value of the variable for which the equation is true.