I need help please help

Here is their argument. given the obtuse angle x, we make a quadrilateral abcd with ∠dab = x, and ∠abc = 90◦, and ad = bc. say the perpendicular bisector to dc meets the perpendicular bisector to ab at p. then pa = pb and pc = pd. so the triangles pad and pbc have equal sides and are congruent. thus ∠pad = ∠pbc. but pab is isosceles, hence ∠pab = ∠pba. subtracting, gives x = ∠pad−∠pab = ∠pbc −∠pba = 90◦. this is a preposterous conclusion – just where is the mistake in the "proof" and why does the argument break down there?

The equation of a circle is (x + 4)2 + (y + 6)2 = 16. determine the length of the radius. 10 4 16 8 my flower basket delivers flowers within a 20 mile radius of their store. if this area is represented graphically, with my flower basket located at (5, 2), what is the equation that represents the delivery area? (x - 2)2 + (y - 5)2 = 20 (x - 5)2 + (y - 2)2 = 20 (x + 5)2 + (y + 2)2 = 400 (x - 5)2 + (y - 2)2 = 400

Can someone me out here number 4 plz