State whether the following quadratic equations have two distinct real roots. Justify your answer.
(x + 1) (x - 2) + x = 0
The equation (x + 1) (x - 2) + x = 0 has two real and distinct roots.
Simplifying the above equation,
⇒ x2 + x – 2x – 2 + x = 0
∴ x2 – 2 = 0
∴ D = b2 - 4ac
= (0)2 - 4(1) (-2)
= 0 + 8 > 0
Hence, the roots are real and distinct.