Hey! What’s the composite figure ? Thanks ! No links please.

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?

Clara solved the equation 7/3x = −2/3 as shown → 7/3x( 3/7 ) = −2/3 ( 3/7 ) x = −14 what is clara’s error?

Consider 6x2 + 6x + 1. which term immediately tells you that this expression is not a perfect square trinomial? justify your answer