If x is greater than or equal to 25 and y is less than or equal to 40

Linear Equations

If x is greater than or equal to 25 and y is less than or equal to 40, then which one of the following is always correct?

  1. x is greater than y
  2. (y - x) is greater than 15
  3. (y - x) is less than or equal to 15
  4. (x - y) is greater than or equal to 65

Answer

x ≥ 25

y ≤ 40 or -y ≥ -40

Adding both inequalities,

(x - y) ≥ 25 - 40

(x - y) ≥ -15

(y - x) ≤ 15

The correct option is C.