Multiple choice

Given below are three statements. A. Statement 1: Solution for x2 + 9x – 36 = 0 is (x = 3 & x = -12) B. Statement 2: x2 + 5x + 50 = 0 has no real roots. C. Statement 3: In equation, x2 + 7x + 10 = 0, one root is double of other. Which of the following is correct?

  1. (A), (B) and (C)

  2. (A) and (C) only

  3. (A) and (B) only

  4. Only (A)

  5. NA
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Statement 1: x^2 + 9x - 36 = (x+12)(x-3) = 0, roots are -12 and 3. Correct. Statement 2: Discriminant D = 5^2 - 4(1)(50) = 25 - 200 = -175. Since D < 0, there are no real roots. Correct. Statement 3: x^2 + 7x + 10 = (x+5)(x+2) = 0, roots are -5 and -2. -5 is not double -2. Incorrect.

AI explanation

For statement A, the roots of x2 + 9x - 36 = 0 are found by factoring to (x + 12)(x - 3) = 0, which gives x = 3 and x = -12, making it correct. For statement B, the discriminant of x2 + 5x + 50 = 0 is (5)2 - 4(1)(50) = -175, which is less than zero, so it has no real roots and the statement is correct. For statement C, the roots of x2 + 7x + 10 = 0 are -2 and -5; since -5 is not exactly double -2, the statement is false. Therefore, only statements A and B are correct.

Keep practicing — related questions