Question

Which set of points contains the solutions to the inequality y ≤ 8x – 3? A. {(–3,–17), (4,11), (7,19)} B. {(3,22), (2,3), (8,27)} C. {(4,29), (–6,–58), (7,19)} D. {(–2,–18), (4,37), (5,15)}

Answer 1

Just to clarify, here are the answer choices:

A. {(–3,–17), (4,11), (7,19)}

B. {(3,22), (2,3), (8,27)}

C. {(4,29), (–6,–58), (7,19)}

D. {(–2,–18), (4,37), (5,15)}

And all of the points in the set must satisfy y ≤ 8x – 3.

The only way is to go through each answer choice, eliminating each that is wrong.

A) -17 ≤ -3*8-3

-17 ≤ -21 ✘

B) 22 ≤ 3*8-3

22 ≤ 21 ✘

C) a) 29 ≤ 8*4-3

29≤29 ✔

   b) -58 ≤ 8*(-6)-3

-58 ≤ -49 ✔

   c) 19 ≤ 7*8-3

19 ≤ 53  ✔

It becomes clear that the answer is C. But just to make sure, we must check D to make sure C is really the answer.

D) -18 ≤ 8(-2)-3

-18 ≤ -19 ✘

That means that C is the answer.