1. 1 block 1 block You walk directly east from your house one block. How far from your house are you? You walk directly west from your house one block. How far from your house are you? It didn't matter which direction you walked, you were still 1 block from your house. This is like absolute value. It is the distance from zero. It doesn't matter whether we are in the positive direction or the negative direction, we just care about how far away we are. 4 = 4 4 units away from 0 4 units away from 0 4 =4 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8

2. x =6 What we are after here are values of x such that they are 6 away from 0. x = 6 or x = 6 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 6 and -6 are both 6 units away from 0 x + 4 = 10 The "stuff" inside the absolute value signs could = 10 (the positive direction) or the "stuff" inside the absolute value signs could = -10 (the negative direction) x + 4 = 10 x + 4 = 10 x = 6 or x = 14 Let's check it: 6 + 4 = 10 14 + 4 = 10 10 = 10 10 = 10

3. Let's look at absolute value with an inequality. x 5 In interval notation: (,5) or (5, ) x So if we have x > a it is equivalent to < a or x > a

6. 1 2x 3 3 We must first isolate the absolute value. +3 +3 This means if there are other things on the 6 left hand side of the inequality that are outside of the absolute value signs, we must get rid of them first. From what we saw previously, the "stuff" 1 2x 6 inside the absolute value is either less than or equal to -6 or greater than or equal to 6 Isolate x, remembering that if 1 2 x 6 or 1 2 x 6 you multiply or divide by a negative you must turn the sign. 2 x 7 2x 5 We are dividing by a negative -2 -2 -2 -2 so turn the signs! 7 5 ] [ x or x 2 2 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8