To solve this, we will use the slope formula
From the question, slope = -6 x₁=5 y₁=u x₂ =6 y₂=-2
substitute the values into the formula and solve for u
-6
Add 2 to both-side of the equation
-6 + 2 = -u
-4 = -u
Multiply through by -1
4 = u
Therefore the value of u is 4