Question

1)25x^2-100=0
2)25x^2+100=0
3)25x^2-100x=0
4)25x^2+100x=0

Answer 1

$1)25x^2-100=0 \ 25*(x^2-4)=0 \ x^2-4=0 \ x^2=4 \ x_1=2;x_2=-2 \ 2)25x^2+100=0 \ 25*(x^2+4)=0 \ x^2+4=0 \ x^2=-4$
Нет решений.
$3)25x^2-100x=0 \ 25x*(x-4)=0 \ x_1=0;x_2=4 \ 4)25x^2+100x=0 \ 25x*(x+4)=0 \ x_1=0;x_2=-4$