15x^2 – 7x – 2?

Answer 1

Factor: 15x² - 7x - 2

~ Grouping Number Method for Factoring Trinomials of the Form ax² + bx + c ~
1) Obtain the grouping number "ac".
The grouping number is (a)(c) = (15)(2) = 30
2) Find the factor pair of the grouping number whose sum is "b".
The factor pais of 30 are: 30 * 1, 15 * 2, 10 * 3, and 6 * 5. Now, b = 7, so we want to find the factor pair whose sum is -7. We'll choose 10 and 3 because (-10) + (3) = -7.
3) Use those two factors to wite "bx" as the sum of two terms.
We use the numbers 10 and 3 to write 7x as the sum of (-10x) and (3x).
15x² - 7x - 2 = 15x² - 10x + 3x - 2
4) Factor by grouping.
15x² - 10x + 3x - 2 = 3x(5x + 1) - 2(5x + 1)
= (5x + 1)(3x - 2)

Answer 2

Another case of factorisation. Why doesn't anyone see 'similar questions'?
To factorise 15x^2 – 7x – 2, you need to split the middle term -7x into two appropriate terms. How to get those terms? Here's how:
First multiply the coefficient of the first term with whatever the last term is
15*(-2) = -30
Now you need to find 2 factors of -30 whose product is -30 and whose sum is -7.
From the above data, we can conclude that the larger factor is negative and the smaller term is positive. This will make the search considerably easier.
-30 = 1*-30
2*-15
3*-10
Though there are more factors, we stop here as we have our numbers
3*-10 = -30
3-10 = -7
Split terms: -7x = 3x - 10x
Now to factorise the polynomial
15x^2 – 7x – 2 = 15x^2 + 3x - 10x - 2
= 3x (5x + 1) - 2(5x + 1)
= (3x - 2)(5x + 1)

Answer 3

15x^2–7x–2
=15x^2–10x+3x–2
=5x(3x-2)+1(3x-2)
(5x+1)(3x-2)

Answer 4

factor?
(5x+1)(3x-2)

Answer 5

(5x+1)(3x-2)