When i brake at speeds over 50 my car shake and just last week as i was acclerate it does the same as if i was braking

 

Warped rotors probably.

 

Or, it could also be one of the following:

1. Uneven pads wear-related to warped rotors(in case if the rotors are warped or the pads have worn unevenly, replace both components).
2. Loose suspension components/hardware.
3. Worn/cheap tyres or alignment out-of-spec. Visually check the tyres to see if you can find something unusual (uneven tread wear, missing treads, etc...). Ensure tyre pressures are within the specified range.

Let us know if you need further assistance. With the info you've provided, this is the best I can do for now.


JPN