On amber’s math test, she was asked whether the equation x=1/2y^2 represents a function. if u need a picture to solve there is one amber concluded that the equation represents a function. which additional point could be added to the graph to show amber that the equation does not represent a function? a. (–2, 2) b. (0, 0) c. (8, –4) d. (8, 8)

Which number is irrational? a) 16 b) 18 c) 25 d) 36

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?

What is the interquartile range of this data set? 2, 5, 9, 11, 18, 30, 42, 48, 55, 73, 81