Find k, if one of the roots of x2 + 3(k + 2)x — 9 = 0 is —3.
One of the root of equation x2 + 3(k + 2)x — 9 = 0 is – 3 which means x = – 3 is a root
As x = – 3 is a root of x2 + 3(k + 2)x — 9 = 0 hence x = – 3 will satisfy the equation x2 + 3(k + 2)x — 9 = 0
Put x = – 3 in equation x2 + 3(k + 2)x — 9 = 0
⇒ (– 3)2 + [3 × (k + 2) × (– 3)] – 9 = 0
⇒ 9 + (– 9) × (k + 2) – 9 = 0
⇒ (– 9) × (k + 2) = 0
⇒ k + 2 = 0
⇒ k = – 2
AI is thinking…
Couldn't generate an explanation.
Generated by AI. May contain inaccuracies — always verify with your textbook.