What is the discriminant of $3x^2 - 5x + 4 = 0$ ?

73Correct answerYour answer13Correct answerYour answer23Correct answerYour answer

-23

Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer D

Correct answer: D

Discriminant $= b^2 - 4ac$ with $a = 3$ , $b = -5$ , $c = 4$ .
$= 25 - 4 \times 3 \times 4 = 25 - 48 = -23$ .

Worth noting

13 uses $b^2 - 4c$ (the $a$ is missing), and 73 adds $4ac$ instead of subtracting it. A negative discriminant is perfectly possible: it means no real roots.

Concept: Computing the discriminant
Typical timeTypical: 40 s
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What is the discriminant of 3x2−5x+4=03x^2 - 5x + 4 = 03x2−5x+4=0?

Explanation

What is the discriminant of $3x^2 - 5x + 4 = 0$ ?