What are the roots of $x^2 - 7x + 12 = 0$ ?

-4

and

-3

Correct answerYour answer2 and 6Correct answerYour answer

-3

and 4Correct answerYour answer3 and 4Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer D

Correct answer: D

Find two numbers with product 12 and sum 7: they are 3 and 4.
So $x^2 - 7x + 12 = (x - 3)(x - 4) = 0$ .
Hence $x = 3$ or $x = 4$ .

Worth noting

2 and 6 have the right product but add to 8. $-4$ and $-3$ would come from $x^2 + 7x + 12$ : the signs of the roots are opposite to the signs in the brackets.

Concept: Solving a quadratic by splitting the middle term
Typical timeTypical: 40 s
Your timeYours: —

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What are the roots of x2−7x+12=0x^2 - 7x + 12 = 0x2−7x+12=0?

Explanation

What are the roots of $x^2 - 7x + 12 = 0$ ?