2016 · Q38
Which of the points P(5, -1), Q(3, -2) and R(1, 1) lie in the solution of the system of inequations x + y ≤ 4 and x - y ≥ 2
Elementary MathematicsAlgebra
- AQ and R only
- BP and R only
- CP and Q only
- DP, Q and R
Explanation
P(5,−1): 5−1 = 4 ≤ 4 and 5+1 = 6 ≥ 2 — satisfies both. Q(3,−2): 3−2 = 1 ≤ 4 and 3+2 = 5 ≥ 2 — satisfies both. R(1,1): 1+1 = 2 ≤ 4 but 1−1 = 0 < 2 — fails the second. Hence P and Q only, option C.