Help!!

[whoasailor]

I have a problem and a solution but no idea on how to get from one to the other. Please help!

4(2x+7)(x-3)²+2(2x+7)²(x-3)



Solution:



= 2(2x+7)(x-3)[2(x-3)+(2x+7)]

= 2(2x+7)(x-3)(2x-6+2x+7)

= 2(2x+7)(x-3)(4x+1)

 

[stapel]

What are the common factors in the two terms 4 (2x + 7) (x - 3)² and 2 (2x + 7)² (x - 3)?

When you take those common factors out front, what is left?

Eliz.

 

[Denis]

I have a problem and a solution but no idea on how to get from one to the other. Please help!
4(2x+7)(x-3)²+2(2x+7)²(x-3)
Solution:
= 2(2x+7)(x-3)[2(x-3)+(2x+7)]
= 2(2x+7)(x-3)(2x-6+2x+7)
= 2(2x+7)(x-3)(4x+1)

As stapel told you, you need to take the common factor;
but that's fairly hard to "see" in above.

your expression: 4(2x + 7)(x - 3)² + 2(2x + 7)²(x - 3)
Try it this way:
let a = 2x + 7 and b = x - 3; then equation becomes:
4ab^2 + 2a^2 b
Now you can see that 2ab is common to both, so:
2ab(2b + a)

Now resubtitute a = 2x + 7 and b = x - 3.
Ok Popeye ? :wink: