Motorola modem wireless Mbps dropping…. a lot.

I just upgraded my internet to 50mbps from comcast. Also using a Motorola Surfboard SBG6580 modem. I did a test with my ethernet core and I’m getting the full 50 and sometimes more. But, when I connect to wifi in the other room which is not even 15 feet away, my speed drop to 8! and sometimes 2. Any reason why this i happening ? I know it will drop if I go wireless but I didnt imagine all the way down to 2! any suggestion? :/
Answer #1
U using a Wifi extender ?
if not buys a couple and plug in power point/s where needed to boost signal
Answer #2
No I have not. I would be surprised if i need one, I mean the modem is top of the line from Motorola and i’m not even that far away from it I just dont understand.
Answer #3
Walls (and furniture) make the biggest difference in WiFi, you want to go through as few of them as possible. So get both antennas in a better placement.
Also make sure you don’t have any other wireless equipment at 2.4 GHz near the networking gear.