Answer:
[tex](x-3)(-7x^2+3)[/tex] is the resulting expression after grouping
Step-by-step explanation:
Given:
[tex]-7x^3+21x^2+3x-9[/tex]
Now taking common [tex]-7x^2[/tex] from 1st 2 numbers and and 3 common from last we get
[tex]-7x^2(x-3)+3(x-3)[/tex]
Now taking x-3 common from both numbers we get
[tex](x-3)(-7x^2+3)[/tex] which is the final equation after grouping