ACT Preparation / Unit 8 ACT 0708 short lesson, about 20 seconds
Factoring x² + bx + c
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The idea
To factor x² + bx + c, find two numbers with product c and sum b; the factors are x plus each number.
In practice
x² − x − 12: −4 and 3 multiply to −12 and add to −1, so (x − 4)(x + 3).
Where people slip
A positive c means the numbers share a sign; a negative c, opposite signs.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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