Question

What value of x is in the solution set of 9(2x + 1) < 9x - 18?

-4
-3
-2
-1

Answer 1

Explanation:

9(2x + 1)<9x - 18

18x + 9 < 9x - 18

18x - 9x < - 18 - 9

9x < 27

x = 27/9

x = 3.

Answer 2

The only possible answer that is correct is the first one, x = -4.

Explanation:

Simplify the given inequality as much as possible, and then substitute each of the given x values one by one to determine which is in the solution set.

9(2x + 1) < 9x - 18 becomes 18x + 9 < 9x - 18, which, if reduced by dividing all four terms by 9, becomes 2x + 1 < x - 2.

Simplifying further, we get x < - 3. The only possible answer that is correct is the first one, x = -4. -4 < -3 is true.