Question

What ordered pair doesn't belong in the solution set of y>2x+1? (1,4), (1,6), (3,8), (2,5)?

Answer 1

Put the coordinates of the points to the inequality and check.

y > 2x + 1

for (1, 4):

4 > 2(1) + 1

4 > 2 + 1

4 > 3   CORRECT

for (1, 6):

6 > 2(1) + 1

6 > 2 + 1

6 > 3   CORRECT

for (3, 8):

8 > 2(3) + 1

8 > 6 + 1

8 > 7   CORRECT

for (2, 5):

5 > 2(2) + 1

5 > 4 + 1

5 > 5   FALSE

Answer: (2, 5).