When a transversal is perpendicular to two parallel lines, all the angles formed measure 90. Explain why

Question

Hello I have no further explanations

 

Answer 1

The answer is right that perpendicular angles are simply, by their definition, 90 degree angles.  Any further explanation would just be an extrapolation on that idea.  But if it helps you clarify, you can think about taking the crossed lines and inscribing them with a circle.  A circle has 360 degrees as its arc length (again, by definition), then, since the crossed perpendicular lines create four equal quadrants of that circle, each quadrant must have a 90 degree angle (360 degrees divided by 4).  This is really just restating the question, but a lot of math is like this... simply true by its definition.  

Answer 2

It is because perpendicular lines always form 90 degrees.  That is a geometric fundamental.