Question

B)When ABCD is drawn to scale, would

the lines AD and BC be parallel or not?
You must justify your answer without
using a scale drawing.

Answer 1

Hi there there's several ways this could be proven one way us to consider the allied angle theory where two angles formed between parallel lines are supplementary which in this case can be proven by

2(45)+90=180⁰ ✔

or 3(45)+45=180⁰✔

this would not be the case if it wasn't parallel

Consequently, you can also use the alternate angle theory where you essentially extend one of the lines and you'll see two equal alternate angles