Placement Games Are Frustrating

Okay. So I started doing ranked and I am trying to complete my 10 games so I can get placed. However I feel like I am gonna be placed low because of toxic teammates. On average I go X/4/X as Support. No matter how many times I help the AD win bot lane, we still end up losing the game because of people going AFK, disconnection issues or going 0/X/X. This makes me mad cause I was really looking forward to ranked. Will losing all of my placement games put me at the bottom of bronze?