8

Set 5: Quadratic Equations (Advanced)

Explanation

Answer: A

Calculate the discriminant of x24x+3=0x^2 - 4x + 3 = 0.

A.

4

✓ Correct
B.

12

C.

-4

D.

28

Detailed Explanation

Choice A is correct. Choice A is the correct answer. The discriminant formula is Δ=b24ac\Delta = b^2 - 4 ac. 1. Identify coefficients: a=1a = 1, b=4b = -4, c=3c = 3. 2. Substitute: Δ=(4)24(1)(3)\Delta = (-4)^2 - 4(1)(3). 3. Calculate: Δ=1612=4\Delta = 16 - 12 = 4. Choice B is incorrect because it calculates 4ac4ac only. Choice C is incorrect because it subtracts in reverse (121612 -16). Choice D is incorrect because it adds (16+1216 +12).

Key Steps:

The correct answer is 4

Why others are wrong:
B: Choice B is incorrect and may result from a calculation error.
C: Choice C is incorrect and may result from a calculation error.
D: Choice D is incorrect and may result from a calculation error.

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