SOLUTION: Please, help me factorise: 2x2 - 8 - (x + 2)(-2x + 6)

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Question 927164: Please, help me factorise: 2x2 - 8 - (x + 2)(-2x + 6)
Found 2 solutions by MathLover1, Edwin McCravy:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

2x%5E2-8-%28x+%2B+2%29%28-2x+%2B+6%29
2x%5E2-8-%28-2x%2Ax+%2B+6%2Ax%2B2%28-2x%29%2B2%2A6%29
2x%5E2-8-%28-2x%5E2+%2B+6x-4x%2B12%29

2x%5E2-8%2B2x%5E2-6x%2B4x-12
%282x%5E2%2B2x%5E2%29%2B%284x-6x%29-%2812%2B8%29
4x%5E2-2x-20...simplify;all terms could be divided by 2
4x%5E2%2F2-2x%2F2-20%2F2
2x%5E2-x-10...factor; write -x as -5x%2B4x
2x%5E2-5x%2B4x-10
%282x%5E2-5x%29%2B%284x-10%29
x%282x-5%29%2B2%282x-5%29
%28x%2B2%29%282x-5%29

Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
2x² - 8 - (x + 2)(-2x + 6)

2(x² - 4) - (x + 2)(-2x + 6)

Factorise x² - 4 as (x - 2)(x + 2)

Factorise -2x + 6 as -2(x - 3)

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

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

2(x + 2) is a common factor of bath as you see by the red coloring:

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

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

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

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

Without the red coloring:

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

Edwin