-7X + 9 In the expresion show, which of the following is the variable

x

Step-by-step explanation:

x

Step-by-step explanation:

the variable is always a letter and in this case it's x, but you''ll see others like a, b, c, anything really.

options a,b,c are the right answer.

step-by-step explanation:

a linear parent function is always represented as y = x

if we write this function in the form of y=mx+c

⇒

or  

now if we plot a graph we will find these characteristics:

1) y intercept of the graph is zero so its a straight line passing through origin.

2) as we can see in both the forms of function written, values of x and y may be either positive or negative for the positive slope means points on the graph are either in first quadrant or in third one.

3) it's slope is one.