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1) Can the below be factored since it does not have all like characters? 4a^2 + 16ab + 16b^2
Yes it can be factored.
4a^2 + 16ab + 16b^2 = (2a + 4b)^2.
2) Also, have I correctly factored ax^2 -a = To be a(a+1)(a-1)
Your "factoring" is WRONG.
The correct factoring is ax^2 -a = a*(x+1)*(x-1).
Solved and answered.
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By the way, when you pose your question this way
Can the below be factored since it does not have all like characters?
4a^2 + 16ab + 16b^2
you make several logical/mathematical errors simultaneously.
First is that " it does not have all like characters ".
In contrary, it has the common factor 4.
Second, in order for an expression could be factored, it is NOT NECESSARY to have all like characters:
a^2 - b^2 = (a+b)*(a-b).