Maths And Technology: calculating angles of mirrors for a laser.

HELP// maths and technology(light) hello! So, I have a class project in which we have to secure a piece of art in a 'museum'. In this project we have to use a laser, 2 mirrors and a sensor (basic things). They have given us coordinates of the places where these will go: LASER(0,0) MIRROR1(5,60) MIRROR2(110,40) and SENSOR(90,15). This is on a normal coordinate system. Now, we have to calculate the angles on which our mirrors will stand. we also have to calculate the angle of the laser. our laser will then have to reach the sensor passing through the lasers. For info: i am in 9th grade so the mathematics level isn't very high. we've learned the PYTHAGORAS THEORY, sin cos tan and functions y=ax+b... and much more

thank you if you help me, i will greatly appreciatie it.

The law of relection is ... incident and reflected angles are equal.

Join the points by straight lines which are the incident and reflected rays. Draw their bisectors which are normal to the mirrors. Draw short perpendiculars to each of four normals which now represent the mirrors.