Answer:
 y = (5/4)x + 6
Explanation:
The 1st line's equation is:
● 4x + 5y = 20 
Substract 4x from both sides 
● 4x + 5y - 4x = 20 - 4x 
● 5y = 20 -4x 
● 5y = -4x + 20 
Divide both sides by 5 
● 5y/5 = (-4x + 20)/5 
● y = (-4/5)x + 4 
● y = -0.8x + 4 
Let m be the slope of the second line 
The lines are perpendicular so the product of their slopes equals -1
Then: m × (-0.8) = -1 
● m × (-0.8)= -1 
● m = -1/(-0.8) 
● m = 1.25 
y = 1.25x + b 
b is the y-intercept of the line.
To get it replace by the coordinates of a point.
We are given that the line passes through (-4,1)
● y = 1.25x + b 
● 1 = 1.25 × (-4) + b 
1.25 is 5/5 
● 1 = (5/4) × (-4) + b
● 1 = -5 + b 
Add 5 to both sides 
● 1 + 5 = -5 + b + 5 
● b = 6 
So the equation is 
● y = (5/4)x + 6