Question

Find k if x = 3 is a root of equation kx² – 10x + 3 = 0.

Answer 1

Given x = 3 is a root of equation kx² – 10x + 3 = 0

So, x = 3 must satisfy the given quadration equation.  

k(3)² – 10(3) + 3 = 0

⇒ 9k – 30 + 3 = 0

⇒ 9k – 27 = 0

⇒ 9k = 27

⇒ k = `27/9`

⇒ k = 3