Question

Solve the following quadratic equation:

100x² – 20x + 1 = 0

Answer 1

We write, –20x = –10x – 10x as 100x² × 1 = 100x² = (–10x) × (–10x) 

∴ 100x² – 20x + 1 = 0 

⇒ 100x² – 10x – 10x + 1 

⇒ 10x(10x – 1) – 1(10x – 1) = 0 

⇒ (10x – 1) (10x – 1) = 0 

⇒ (10x – 1)² = 0

⇒ 10x – 1 = 0 

⇒ `x = 1/10` 

Hence, `1/10` is the repeated root of the given equation.