Your rotors need to be turned. They have become warped.
vacuum leak 65 power brakes run off a vacuum, when you apply your brakes you stop the air leak. 65;
If the rotors are warped it can cause a shake when you hit the brakes.
Foot brakes are used to stop a car. In an emergency however both the foot and hand brakes can be used to stop a car.
Applying the brakes with your foot!
have your front brakes checked
yes
yes, but only when the brakes are applied.
no
Warped brake rotors........
rear brake drums or rotors are out of round.
Your brake rotors are warped and need replaced/resurfaced.
Vibration when applying brakes is most likely warped rotors. Another cause could be loose caliper bolts.