Well, a linear equation should look like this: y = ax + b.
So if the slope is 0, then y = a*0 + b = b.
If y = b, then the line is a horizontal line like this: ______________
Now, we look at the points that were given in the question: (-2, 7), (2, -5)
If the slope is 0, then the value of y, should not change, but the value of x will constantly be changing. So it means that as x increases, y is always the same.
If we look at the y place on the points: The y values are the bold numbers:
(-2, 7), (2, -5)
As you can see, 7 is not the same as -5. So the line's slope is not 0. The slope would be a negative number. Why? Well, 7 is above the x-axis and -5 is below the x-axis. For the x values, -2 is smaller than 2, so the point (-2, 7) is located at the top left quadrant and the point (2, -5) is located at the bottom right quadrant.
So to answer your question, the slope is not zero. The slope is negative.
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