It is called zero or root of the polynomial function of the first degree f (*x*) = a*x* + b, a0, the real number *x* such that f (*x*) = 0. We have:

f (*x*) = 0 The*x* + b = 0

Let's look at some examples:

Obtaining the zero of function f (

*x*) = 2*x*- 5:

f (*x*) = 0 2*x*- 5 = 0Calculation of the root of function g (

*x*) = 3*x*+ 6:

g (*x*) = 0 3*x*+ 6 = 0*x*= -2Calculation of the abscissa of the point at which the graph of h (

*x*) = -2x + 10 cuts the abscissa axis:The point at which the graph cuts the axis of

*x*is one where h (*x*) = 0; So:

H(*x*) = 0 -2*x*+ 10 = 0*x*= 5