Practicing Success
Statement-1 : The plane 5x + 2z - 8 = 0 contains the line 2x - y + z - 3= 0 and 3x + y + z = 5, and is perpendicular to 2x - y - 5z - 3 = 0. Statement-2 : The plane 3x + y + z = 5 meets the line x-1 = y + 1 = z - 1 at the point (1, 1, 1). |
Statement 1 is True, Statement 2 is true; Statement 2 is a correct explanation for Statement 1. Statement 1 is True, Statement 2 is True; Statement 2 is not a correct explanation for Statement 1. Statement 1 is True, Statement 2 is False. Statement 1 is False, Statement 2 is True. |
Statement 1 is True, Statement 2 is False. |
The equation of the family of planes containing the line 2x - y + z - 3 = 0, 3x + y + z = 5 is $2x - y + z - 3 + λ (3x + y + z - 5 ) = 0 $ For $ λ = 1,$ this reduces to 5x + 2z - 8 = 0 So, the plane 5x + 2z - 8 = 0 contains the given line. Also, $ 2 × 5 - 1 × 0 - 5 ×2 = 0 $ So, the plane 5x + 2z - 8 = 0 is perpendicular to 2x - y - 5z - 3 = 0. Hence, statement-1 is true. The coordinates of any point on line $\frac{x-1}{1}=\frac{y+1}{1}=\frac{z-1}{1}$ are (r + 1 , r-1, r+1). If this point lies on the plane 3x + y + z = 5. Then, $3r + 3 + r - 1 + r + 1 = 5 ⇒ r = \frac{2}{5}$ Thus, the line meets the plane at $\left(\frac{7}{5}, -\frac{3}{5}, \frac{7}{5}\right)$. So, statement-2 is not true. |