1. ## factoring

...having some trubles with factoring.

I was wondering if someone could show me how to factor these.

x^2-16

641^2-49y^2

Any help would be appreciated.

2. Originally Posted by smallman_11
...having some trubles with factoring.

I was wondering if someone could show me how to factor these.

x^2-16

641^2-49y^2

Any help would be appreciated.
x^2 - 16

Factoring the above: (x - 4)*(x + 4)...do FOIL (First, Outer, Inner, Last) and check that it works.

641^2-49y^2

Factoring the above: (-7*y + 641)*(7*y + 641); again, check.

3. thanks for the help.

4. Originally Posted by smallman_11
...having some trubles with factoring.

I was wondering if someone could show me how to factor these.

x^2-16

641^2-49y^2

Any help would be appreciated.
When given an expression: $a^2-b^2$ then it factors to: $(a+b)(a-b)$