Multiple choice

Two equations are given as x2 + x + 3 = 0 and 2x2 + 6x + 24 = 0. Add these two equations and then find the value of ab after comparing the resulting equation with the standard quadratic equation ax2 + bx + c = 0

  1. 5

  2. 16

  3. 21

  4. 27
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Adding the equations: (x^2 + x + 3) + (2x^2 + 6x + 24) = 3x^2 + 7x + 27 = 0. Comparing this to ax^2 + bx + c = 0, we get a = 3 and b = 7. The product ab = 3 * 7 = 21.

AI explanation

Adding the two equations x2 + x + 3 = 0 and 2x2 + 6x + 24 = 0 results in 3x2 + 7x + 27 = 0. Comparing this to the standard quadratic equation ax2 + bx + c = 0 gives a = 3 and b = 7. Multiplying these values gives ab = 3 times 7, which is 21.

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