If one root of 2x2 + ax + 6 = 0 is 2 then the value of a is?

If one root of 2x2 + ax + 6 = 0 is 2 then the value of a is?

Explanation

One root = 2  

Equation: 2x² + ax + 6 = 0


Using factor theorem, substitute x = 2:


2(2)² + a(2) + 6 = 0  

⇒ 8 + 2a + 6 = 0  

⇒ 2a + 14 = 0  

⇒ 2a = -14  

⇒ a = -7