Slope of the side DA of the rectangle ABCD is $$\frac{5}{3}$$. What is the slope of the side AB?

In given rectangle
Let $$\square $$ ABCD
Angle of rectangle = 90°
AB ⊥ DA
∴ Slope $$\left[ {{{\text{m}}_1} = \frac{{ - 1}}{{{{\text{m}}_2}}}} \right]$$   (when lines are perpendicular to each other)
Slope of side DA (m₁) = $$\frac{5}{3}$$
Slope of side AB (m₂) = $$\frac{{ - 3}}{5}$$