Answer: y = (-5/4)x - 8
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Step-by-step explanation:
Recall that y = mx+b is the slope intercept form of any linear equation
The given equation has m = 4/5 as the slope. Flip the fraction to get 5/4 and then flip the sign to get -5/4
The original slope is 4/5 and the perpendicular slope is -5/4. Note how the slopes multiply to -1.
The slope for the answer is -5/4 and the y intercept for the answer is -8
Therefore, the perpendicular line is y = (-5/4)x - 8