The sum of two positive integers, x and y, is not more than 40. The difference of the two integers is at least 20. Chaneece chooses x as the larger number and uses the inequalities y ≤ 40 – x and y ≤ x – 20 to determine the possible solutions. She determines that x must be between 0 and 10 and y must be between 20 and 40. Determine if Chaneece found the correct solution. If not, state the correct solution.
Answer
A
Yes, Chaneece found the correct solution.
B
No, Chaneece mixed up the variables. The correct solution is that x must be between 20 and 40 and y must be between 0 and 10.
C
No, Chaneece should not have restricted the solution to quadrant I. The correct solution is that x can be all real numbers and y must be less than 10.
D
No, Chaneece looked at the wrong area of the shaded graph. The correct solution is that x must be between 0 and 30 and y must be between 0 and 40.