Respuesta :

 solve for r.

6qr+7rs−2st=−9

Add 2st to both sides.

6qr+7rs−2st+2st=−9+2st

6qr+7rs=2st−9

Factor out variable r.

r(6q+7s)=2st−9

Divide both sides by 6q+7s.

r(6q+7s) / 6q+7s = 2st−9 / 6q+7s

r = 2st−9 / 6q+7s
6qr + 7rs - 2st = -9
6qr + 7rs = -9 + 2st
r ( 6q + 7s ) = -9 + 2st
r = -9 + 2st / 6q + 7s Ans