WEBVTT

1
00:00:00.000 --> 00:00:05.259
Here is the problem: negative 6x plus 6 less than 8x minus 8.

2
00:00:05.709 --> 00:00:09.505
Solve the inequality and give the answer in interval notation.

3
00:00:10.305 --> 00:00:22.414
Move everything to one side and isolate the variable. Collect terms: negative 14x plus 14 less than 0. Dividing by a negative coefficient reverses the inequality sign.

4
00:00:22.864 --> 00:00:37.667
Test one point in each interval (sign chart). (-∞, 1): test x equals 0 → sign plus → excluded; (1, ∞): test x equals 2 → sign minus → included.

5
00:00:38.117 --> 00:00:41.078
Decide the endpoints. 1: excluded.

6
00:00:41.528 --> 00:00:43.014
Write the solution set.

7
00:00:43.814 --> 00:00:45.962
So the answer is (1, ∞).

8
00:00:46.412 --> 00:01:01.226
The inequality holds exactly for x in (1, ∞). Points where the expression is undefined are never included, and endpoints are included only for less than or equal to or greater than or equal to where the expression equals zero.

9
00:01:02.026 --> 00:01:06.020
x equals 0: does not satisfy the inequality.

10
00:01:06.470 --> 00:01:09.837
x equals 2: satisfies the inequality.
