Question

What is the equation of the function that is graphed as line b?

y = 1/2x - 1
y = 2x + 1
y = 1/2x + 1
y = -4x

Answer 1

Y=1/2x+1. I need to make it longer so blah blah blah.

Answer 2

-- Look at the places where the line crosses the 'x' axis and the 'y' axis.
Between those two points, it goes forward 2 units, but only rises 1 unit.
So the slope of the line is 1/2 .

-- Look again at the point where the line crosses the y-axis.
At that point, y=1 .
That's the "y-intercept".

Now you have the slope and y-intercept of the line.

The equation of ANY straight line is

y = (slope)x + (y-intercept) .

You know what they both are, so you can easily write

y = 1/2 x + 1 .

Is that one of the choices ?
Yes it is.
Good enough for me.
That must be the correct one.

With no "blah blah blah" required.