Any help should be thanked
Draw a point D on the line BC such that AD is perpendicular to BC. Use the formula for area (BC*AD/2=area) to find AD, after that use the Pythagorean theorem (on the triangle ADC) to find CD. Then you find BD=BC-CD and apply the Pythagorean theorem again (on the triangle ADB) to find AB. The perimeter is now AB+AC+BC.