Practice Round Theta Ciphering Mu Alpha Theta National Convention 2004 If 2x – y = -6 and 4x – 3y = -16,find the sum of x and y. Question #1 Theta Ciphering Mu Alpha Theta National Convention 2004 Let A = the slope of the graph of 2x – 5y = 2004 Let B = the slope of the line containing the points (12, 1) and (-6, 7) Let C = the x-intercept of the graph of 2x + 7y = 10 Let D = the y-intercept of the graph of 6x – 5y = 30 Find: ABCD Question #2 Theta Ciphering Mu Alpha Theta National Convention 2004 Find the area of the region determined by the intersection of the graphs of the given system of inequalities: 5 y 9 y 2x 9 x 7 Question #3 Theta Ciphering Mu Alpha Theta National Convention 2004 Consider the following compound function: x, if x 2 g(x) = x2 , if - 5 < x < 2 x, if x -5 Find: g(-2004) – g(-5) + g(-1) + g(25) Question #4 Theta Ciphering Mu Alpha Theta National Convention 2004 Let A = the perimeter of a rectangle whose width is log62 and whose length is log63 Let B = the value of x that satisfies logx100 – logx4 = log x x Find: A+B Question #5 Theta Ciphering Mu Alpha Theta National Convention 2004 Find: the sum of a and b when i 2004 (1 3i)2 (2 i)(3 i) 1 2i 3 4i is written in the form a + bi a, b ; i = -1 Question #6 Theta Ciphering Mu Alpha Theta National Convention 2004 One side of an equilateral triangle is the hypotenuse of an isosceles right triangle. If the altitude of the equilateral triangle is 8 3 , find the length of a leg of the right triangle. Question #7 Theta Ciphering Mu Alpha Theta National Convention 2004 A polynomial P(x) has zeros 1, -1, and 2, each with multiplicity 1, and no other complex zeros. If P(0) = 8, find P(4). Question #8 Theta Ciphering Mu Alpha Theta National Convention 2004 Let A = the length of the major axis of an ellipse whose equation is 4x2 + 25y2 – 100 = 0 Let B = h + k + r, given that (h, k) is the center and r is the length of the radius of the circle defined by the equation x2 + y2 + 6x – 4y – 12 = 0 Find: AB Question #9 Theta Ciphering Mu Alpha Theta National Convention 2004 Evaluate: 50 k1 k1 k1 1 2k 3 2 3 Question #10 Theta Ciphering Mu Alpha Theta National Convention 2004 Let x = the units digit of the sum 1! + 2! + 3! + 4! + . . . + n! + . . . + 2004! x Evaluate: 4 4 x C 2 5 5 x Question #11 Theta Ciphering Mu Alpha Theta National Convention 2004 A parabola with a vertical axis of symmetry has vertex (3, -2) and a x-intercept of 4. If the equation of the parabola is written in the form y = ax2 + bx + c, find the sum a + b + c. Question #12 Theta Ciphering Mu Alpha Theta National Convention 2004 A pair of fair, six-sided dice is thrown. What is the probability that the numbers on the top faces match or the sum of the numbers shown on the dice is at most 6? Mu Alpha Theta National Convention 2004 Theta Ciphering Answers # Practice 1 2 3 4 5 6 7 8 9 10 11 - TB 12 - TB Answer 3 4 49 -1993 627 1 26 5 or or 5.2 5 5 8 2 120 40 2703 Thrown out 6 1 or 0.5 or 50% 2