ASAP PLEASE HELP!! Two trains leave the railroad station at noon. The first train travels along a straight track
at 85 mph. The second train travels at 70
mph along another straight track that makes
an angle of 130° with the first track. At what
time are the trains 320 miles apart? Round
your answer to the nearest minute.

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?

Acylinder and its dimensions are shown. which equation can be used to find v, the volume of the cylinder in cubic centimeters?

Stacey filled her 1/2 cup of measuring cup seven times to have enough flour for a cake recipe how much flour does the cake recipe calls for