<em>y-intercept</em><em> </em><em>is</em><em> </em><em>where</em><em> </em><em>the</em><em> </em><em>line</em><em> </em><em>on</em><em> </em><em>your</em><em> </em><em>graph</em><em> </em><em>crosses</em><em> </em><em>through</em><em> </em><em>the</em><em> </em><em>y-axis</em>
Check the first picture below.
for a parallelogram, it has to have two pairs of parallel sides, so BC || AD and AB || CD.
if two lines are parallel, they have the same slope, namely the <u>same rise and run</u>.
notice, the line BC has a run of 6 and a rise of 1, <u>arrows in red</u>, therefore, AD must also have a run of 6 and a rise of 1, so if we move from A 6 units over and 1 up, we'd end up at point D.
now, for part atop
Check the 2nd picture, in a parallelogram, opposite sides are parallel and opposite angles are equal, so if WLP is 144°, then PNW is also 144°.
in a parallelogram, diagonals bisect each other, so each cut the other in halves, so if PM is 9 then MW is also 9 and thus PW is just 9+9=18.
now, about QRST.
notice what we said about a parallelogram above, thus
so then TQ ==> 2(8) + 12 ==> 16 + 12 ==> 28.
∡Q ==> 8(12) + 13 ==> 96 + 13 ==> 109°.
and since in a parallelogram, adjacent interior angles add up to 180°, then ∡Q + ∡T = 180°.
∡T ==> 180 - 109 ==> 71°.
