If the equation is y= -7, then what is the slope, and what is the y-intercept?

Simple,

this is the equation y=-7

Your y-intercept is -7, there is no slope, it's not increasing or decreasing.

Your slope is nothing (0) and the y-intercept is -7.

This being said, the line will be a horizontal line, going straight across at

-7, forever.

(-7)

Here's the given equation:          y = -7 .

The y-intercept is the value of 'y' when x=0 .
What is the value of 'y' when x=0 ?

Here, let me give you a hint:  The equation is        y = -7 .
What is the value of 'y' when x=0 ?

The equation says that 'y' is always -7.
It doesn't CARE what 'x' is.  'y' is ALWAYS  -7 .
So when x=0, 'y' is -7.  That's the y-intercept.

Now, how about the slope of the graph ?

You're used to seeing      y = (slope) x + (y-intercept)

                             or          y =        m x   +    b

But this equation only has  y =  b .
It has no  ' m x ', so you don't know how to handle it.

Here, let me help.
I'll re-write the equation, without changing it, and when I do that,
I expect to see you slap yourself in the forehead.

The equation, in its original form:      y  =          - 7

The equation, re-written:                    y  =  (0)x  -  7

Did the light-bulb go on yet ?

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