Question

x^2-70x-9800=0

Answer 1

x^2-70x-9800=0
x^2-140x+70x-9800=0
x(x-140) +70(x-140)=0
(x-140)(x+70)=0
thus x-140=0 or x=140
also may be (x+70)=0 or x=-70
henc x=140,-70

Answer 2

ok thank you got it now.