<span>5(-4) + 2y = -20
-20 + 2y = -20
2y = -20 + 20
2y = 0
y = 0</span>
Trapezoid:
•Can have congruent diagonals. •Has one pair of opposite, parallel sides.
Kites:
•Has congruent adjacent sides.
•Has perpendicular diagonals.
Under a counterclockwise rotation about the origin of 90°
a point (x , y ) → (- y, x ), hence
A(2, 1 ) → A'(- 1, 2 )