KEY Math 110, 111 Practice Quiz # 3 – Sections 2.1-2.4 Algebraic Expressions and Formulas, Simplifying Expressions, Coordinate Plane, Graph of an Expression 1. Evaluate the expression. Simplify to lowest terms when necessary. Round answers to the nearest hundredth if necessary. y y1 a. 2 ; x1 = 3, x2 = -2, y1 = -4, y2 = -5 1/5 x2 x1 b. 2x 2 3x 5 for x = 3 c. –x2 + y; for x = -3, y = -5 d. –x2 + y; for x = 5, y = -2 14 or 3.74 -14 -27 2. The temperature in Thailand is 30o Celsius. To convert to Fahrenheit use the formula F = 9/5 C + 32. What is the Fahrenheit temperature? 86o F 3. Simplify the expression. a. 6x2 + 2x + 3 + 4x2 – 3x – 5 b. –(2a + 3) – (5a – 4) 10x2 – x – 2 -7a + 1 4. Translate the given information into an equation. Let x represent the unknown number and then solve for x. a. Decreasing a number by 20% results in 60. b. A number is increased by 1/3 of the number and the result is 20. c. The quotient of twice a number and 4 is 10. n – .20n = 60; 75 n + 1/3n = 20; 15 2n/4 = 10; 20 5. Plot the points associated with the given ordered pairs. a. A (2, 4), B (-3. 5), C (-2, -5) b. A (1, -3), B (0, 5), C (-2, 0) c. A (0, 0), B (4, -3), C (-2, -3) d. A (5, 4), B (5, -4), C (-5, 4) KEY 6. Refer to the coordinate plane shown and determine the coordinates of the points. a. A (-2, 4) b. B (0, 2) c. C (-2, 1) d. D (-3, -2) e. E (0, -4) f. F (-3, 0) 7. Name the quadrant in which each point lies. a. P ( -2, 5 ) Q II b. Q ( 4, 1/5 ) QI c. R ( - 3 , - 5 ) Q III d. S ( x, y ), y < 0, x = 5 Q IV 8. On a grid map with coordinates in miles, your house is located at ( 4, 6 ). Your school is located at ( -5, 2 ). 97or 9.8miles a. How far is it from your house to your school? b. What are the coordinates of the midway point from your house to your school? ( -1/2, 4 ) 9. Evaluate the expression for the given values using your calculator. Fill in the table of x, y values a. y = 2x + 3 b. y = x2 – 4; c. y = 7 – 4x x 2x + 3 x x2 – 4 x 7 – 4x -1 1 -1 -3 -1 11 2 7 -4, 4 12 0 7 5 13 5 21 5 -13