Answer:
(a) x=45°
(b) If AD was parallel to BC, <A would be equal to (180-<B)=90 (corresponding angles). Since <A≠90, we can see that AD and BC aren't parallel.
Step-by-step explanation:
(a)
Angles in a quadrilateral add to 360:
<A+<B+<C+<D=360
2x+90+x+3x=360
6x=270
x=45°
(b)
If AD was parallel to BC, <A would be equal to (180-<B)=90 (corresponding angles). Since <A≠90, we can see that AD and BC aren't parallel.
