I just got my tires rotated. My steering wheel shakes at speeds 70+ Mph and car brakes make car shakes, why?

have those front tires checked again for balance as it almost sounds like a belt might have shifted in one of the tires, thats the first thing I would check, then have all the steering parts checked for looseness, if your getting a shaking when you hit the brakes also, you could have warped brake rotors causing that problem.