Respuesta :

ali3049

they all multiple by 4 like y 2/4+ 4y- 21

PeshwaBajirao42

(4)(y^2+4y-21)=0

BY MIDDLE TERM SPLITTING

(4){y^2+(7y-3y)-21}=0

(4)(y^2+7y-3y-21)=0

(4){(y^2+7y)-(3y+21)}=0

(4){y(y+7)-3(y+7)}=0

(4)(y-3)(y+7)=0

HOPE THIS WILL HELP U