Question

How to find the factor form of 28n^4+16n^3-80n^2=0

Answer 1

you want to find the largest factor of n, in common with all terms

we can start by taking out a factor of n at a time
factor out n

n(28n^2 +16n^2-80n)=0
but you can still take out an n since they are all still multiplied by n
n(n(28n+16n-80))=0
you can't take any more factors of n out of these numbers, since -80 is not multiplied by any n
so you have n(n)(28n+16n-80)=0
nxn=n^2

n^2(28n+16n-80)=0

now, find a number that goes into 28, 16, and -80. you want the largest number you can find
I would start with 4
and factor out 4
n^2(4(7n^2+4n-20))=0
4n^2(7n^2 +4n -20))=0

now you want to factorise 7n^2 +4n -20

7n(n+2)-10(n+2)

so your final answer will be

4n^2(7n-10)(n+2)

Answer 2

that should be 4n^2(7n-10)(n+2)=0

Answer 3

Thanks so much