help me on my algebra?

Question

factor 15n^2-19n-10
15x^2+19x-10
15x^2-19x+6

Answer 1

15n² - 19n - 10

15n² - 25n + 6n - 10

5n(3n - 5) + 3(3n - 5)

(5n + 3)(3n - 5)

- - - - - - - - - - - - -s-

Answer 2

Here are your answers.

15n^2-19n-10 = (5n + 2)(3n - 5)

15x^2+19x-10 = (5x- 2)(3x + 5)

15x^2-19x+6 = (5x - 3)(3x - 2)


The key to solving these problems is looking at the factors of the first and last terms. Once you have all the factors writen down (for 15 it would be 1 & 15, and 3 & 5), look at the positive and negative signs in the function and try to get them to fit. Often times it's just guess and test.

Answer 3

These problems require some trial & error, and a little experience helps too!

A. First, factor the coefficient of n^2. 15 is broken into 5 and 3.
(5n )(3n )
Since the last number is negative, each set will have a different sign.
(5n+ )(3n- )
Factor 10 into 5 and 2.
(5n+2)(3n-5)
Which when multiplied results in (5n)(3n)+2(3n)-5(5n)-10=
15n^2-19n-10
Knowing which parts to put where is a result of practice, experience, and a good math sense. If you want the middle term to be negative you wanter the larger number to be negative. (Hence the neg. 25 and the pos. 6)

Use similar strategies to work out the others.
B. (3x+5)(5x-2) [very similar]
C. (5x-3)(3x-2) [last number is pos., so either both were negative or both were positve. negative in this case because the middle number had to be negative]

Answer 4

15n^2 - 19n -10 = (3n-5) (5n+2)
15x^2 +19x - 10 = (3n+5) (5x-2)
15x^2 - 19x+6 = (3x-2) (5x-3)

Hope this helps!

Answer 5

1. 15n^2-19n-10
=15n^2-25n+6n-10
=5n(3n-5)+2(3n-5)
=(5n+2)(3n-5)=0
so n=-2\5,5\3
2. 15x^2+19x-10
=15x^2+25x-6x-10
=5x(3x+5)-2(3x+5)

so x=2\5,-5\3

3. 15x^2-19x+6
=15x^2-10x-9x+6
=5x(3x-2)-3(3x-2)

so x=3\5,2\3

Answer 6

(5n + 2).(3n - 5)
(5x - 2).(3x + 5)
(5x - 3).(3x - 2)