Im so sorry.. I did not mean to submit an answer..
And I honestly don't know how to get rid of my answer.. but I will try to help.
4x²- 20x=0 =
= -√5,
= √5
3x²-42=0 =
= -√14,
= √14
2x²-14x=0 =
= 0,
= 7
8x²-98=0 =
= -
,
=
I hope that these are the answers that you wanted, if they are not, I am sorry, tell me and I will try to fix them.