Answer :
Answer:
pairs of factors of +15, sum of +8
Step-by-step explanation:
in factoring trinomials (three terms, in this case being x^2, 6x, and 15), we want our two factors to multiply to equal the final number, so 15. factors of + 15 (positive because 15 has a plus sign before it in the trinomial) are
1 and 15
3 and 5
now which ones of these add to give + 8?
3 and 5
so now the binomials (two terms) are
(x + 3) and (x + 5)
notice how there are 2 terms in these separates by one plus sign, so they are binomials, you can foil to check your work as well
Answer:
See attachments.
Step-by-step explanation:
Question 1
To factor the quadratic expression x² + 8x + 15, we first need to identify the pairs of factors of the product of the coefficient of x² and the constant.
In this case, the coefficient of x² is one and the constant is 15, so their product is 1 × 15 = 15. Therefore, we need to list pairs of factors of 15, which are:
- 1 and 15
- 3 and 5
Next, we need to identify the pair of factors that has a sum equal to the coefficient of the x-term in the quadratic expression. In this case, the coefficient of the x-term is 8, so we need to identify the pair that has a sum of 8. The pair of factors that has a sum of 8 is:
- 3 and 5
To write the quadratic expression as the product of two binomials, rewrite the middle term as the sum of 3 and 5:
[tex]x^2+3x+5x+15[/tex]
Now, factor the first two terms and the last two terms separately:
[tex]x(x+3)+5(x+3)[/tex]
Finally, factor out the common term (x + 3):
[tex](x+3)(x+5)[/tex]
Therefore, the given quadratic expression written as a product of two binomials is:
[tex]\Large\boxed{\boxed{(x+3)(x+5)}}[/tex]
[tex]\dotfill[/tex]
Question 2
To factor the quadratic expression x² + 2x - 15, we first need to identify the pairs of factors of the product of the coefficient of x² and the constant.
In this case, the coefficient of x² is one and the constant is -15, so their product is 1 × 15 = -15. Therefore, we need to list pairs of factors of -15, which are:
- -1 and 15
- 1 and -15
- -3 and 5
- 3 and -5
Next, we need to identify the pair of factors that has a sum equal to the coefficient of the x-term in the quadratic expression. In this case, the coefficient of the x-term is 2, so we need to identify the pair that has a sum of 2. The pair of factors that has a sum of 2 is:
- -3 and 5
To write the quadratic expression as the product of two binomials, rewrite the middle term as the sum of -3 and 5:
[tex]x^2-3x+5x-15[/tex]
Now, factor the first two terms and the last two terms separately:
[tex]x(x-3)+5(x-3)[/tex]
Finally, factor out the common term (x - 3):
[tex](x-3)(x+5)[/tex]
Therefore, the given quadratic expression written as a product of two binomials is:
[tex]\Large\boxed{\boxed{(x-3)(x+5)}}[/tex]