Bell Work:
1. What is the absolute value of 5?
2. What is the absolute value of -4?
3. What is the distance between 2 and 5
on a number line?
4. What is the distance between
-1 and -4 on a number line?
5. What is the distance between -2 and 5
on a number line?
2.5 Solving Equations Involving Absolute Value
Objectives: I can evaluate absolute value expressions.
I can solve absolute value equations.
Equations with an absolute value expression will have two cases.
Absolute value can be interpreted as distance.
Example #1

lxl=4
“the absolute value of what equals 4?”

l y l = 10
Example #2

l f - 5 l = 17
“the distance between the number f and 5 is 17 units”

ly-2l=4
“the distance between the number y and 2 is 4 units”

la+3l=2
“the distance between a and -3 is 2 units”

l b + 1 l = -3
“the distance between the number b and -1 is -3”
Example #3

Ice cream should be stored at 5 F with a margin of error of 5. Write and solve
an equation to find the maximum and minimum temperatures at which the ice
cream can be stored.
Example #4

Write and solve an equation involving absolute value for the graph. Find the point
that is the same distance from 2 as it is from 8.
Homework: 2.5 (pg. 106)
#22,24,25,29,31,34,36,43