Answer mark brainliest if answered now. 20points

how to solve the quadratic equation
4y^2 +16y -84= 0

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

(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

fa tha first one you gonna add y to both sides

it look like this

x-y+y=6+y

x=y+6

therefore your answer is

x =y+6

fa tha second one

you gonna flip tha equation

it gonna look like x-4y=y

then add 4 to both sides

it gonna look like tha

x-4 +4 =y +4

so therefore tha answer is x=y+4

step-by-step explanation: