If y varies directly with x, and y = 8 when x = 2, find the equation of variation.

Step 1 ：Step 1: Since y varies directly with x, we can write this relationship as \(y = kx\), where k is the constant of variation.

Step 2 ：Step 2: Substitute the given values into the equation. We get \(8 = k \cdot 2\).

Step 3 ：Step 3: Solve for k. We get \(k = \frac{8}{2} = 4\).

Step 4 ：Step 4: Substitute k = 4 into the equation \(y = kx\) to find the equation of variation.