factor by grouping: 2x^2 + 10x - 3x - 15?

Answer 1

First: group like terms in parenthesis:

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

Second: factor both sets by finding the least common factor for each parenthesis:

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

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

Answer 2

Look at the first pair of terms and then the second pair of terms and think about what each has in common.
The first pair: 2x^2 + 10x has a 2x in common 2x(x+5)
The second pair: -3x-15 has a -3 in common -3(x+5)
Pull out the common term in each pair
2x(x+5)-3(x+5)
Now there is an (x+5) in common, so take that out.
Answer: (x+5)(2x-3)

Answer 3

1) 2x(x + 5) - 3(x+5) , factor 2x out of 2x^2+10x , and factor 3 out of 3x-15
2) (2x-3)(x+5) group them

Answer 4

2x² + 10x - 3x - 15 = 0
2x(x + 5) - 3(x + 5) = 0
(2x - 3)(x + 5)
2x² + 7x - 15 = 0
7² - 4.2.-15
49 + 120 = 169

x = (-7 +/-\/169) : 2.2
x' = (-7 + 13) : 4 = 3/2 = 1,5
x" = (-7 - 13) : 4 = -20 : 4 = -5
Solution: {x E R | x' = 1,5 or x" = -5}
<><

Answer 5

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

Answer 6

2x^2+7x-15
(2x-3)(x+5)