Why does my toilet bubble when the wash machine drains,what could be the problem,

The most probable cause is that the sewer pipe has some blockage, and the water can not drain fast enough, and as result pushes some of the water backwards towards your toilet, creating bubbles there.
Have an inspection of the sewer done asap before the problem runs out of control !
Do you perhaps have your own septic tank ? Start from there !

Clean your sewer main pipe. Sewage overflow will follow soon.

why does my toilet bubble when the wash machine drains,what could be the problem,,
Bubbles indicate back pressure caused by a partial blockage downstream from the toilet. This cab be resolved by snaking fr5om the lavatory roof vent. Put out enough cable to reach the base and 15 feet more. Good luck, Tom