Dynamic Activity

Factoring x 2 + b x + c x squared , plus b x plus c

Problem 1 Factoring x 2 + b x + c x squared , plus b x plus c  Where b > 0 , c > 0 b greater than 0 comma c greater than 0

What is the factored form of x 2 + 8 x + 15 ? bold italic x squared , plus 8 bold italic x plus 15 question mark

List the pairs of factors of 15. Identify the pair that has a sum of 8.

x 2 + 8 x + 15 = ( x + 3 ) ( x + 5 ) x squared , plus 8 x plus 15 equals open x plus 3 close open x plus 5 close

Check ( x + 3 ) ( x + 5 ) = x 2 + 5 x + 3 x + 15   = x 2 + 8 x + 15 ✓ table with 2 rows and 3 columns , row1 column 1 , open x plus 3 close open x plus 5 close , column 2 equals , column 3 x squared , plus 5 x plus 3 x plus 15 , row2 column 1 , , column 2 equals , column 3 x squared , plus 8 x plus 15 check mark , end table

✓ Got It?

1. What is the factored form of r 2 + 11 r + 24 ? bold italic r squared , plus 11 bold italic r plus 24 question mark