A student had this question on a recent Geometry test: If m_A = (Tx+37º, mZB = (8x – 112° m2C = (5x + 711°, and m2D = (4y - 4), find the values of x and y that
make quadrilateral ABCD a parallelogram. The student's answer was x = 17, y = 7.
The teacher, marked the student's answer incorrect. The student insists it is correct
and would like the teacher to take another look at it. Is the teacher correct in scoring
this answer as incorrect? Explain.

In trapezoid efgh, m∠hef=(4x2+16)∘ and m∠gfe=(5x2+12)∘. find the value of x so that efgh is isosceles.

The fence around a quadrilateral-shaped pasture is 3a^2+15a+9 long. three sides of the fence have the following lengths: 5a, 10a-2, a^2-7. what is the length of the fourth side of the fence?

An automobile assembly line operation has a scheduled mean completion time, μ, of 12 minutes. the standard deviation of completion times is 1.6 minutes. it is claimed that, under new management, the mean completion time has decreased. to test this claim, a random sample of 33 completion times under new management was taken. the sample had a mean of 11.2 minutes. assume that the population is normally distributed. can we support, at the 0.05 level of significance, the claim that the mean completion time has decreased under new management? assume that the standard deviation of completion times has not changed.