Mathematics 10 — Exercise 2.6 · Q3

Full question

Make a the subject of the formula.

Step-by-step solution

1. Subtract (n−1)d, then divide by 2, using the formula exactly as printed.

2. Apply that operation equally to both sides.

   $$2\times a=S-d\times \left(n-1\right)$$

3. Apply that operation equally to both sides.

   $$a=\frac{S}{2}-\frac{d\times \left(n-1\right)}{2}$$

Answer

The final answer is shown below.