Activity 3.1: Solving Absolute Value Equations Homework

Name _________________________
Due Date _____________________
Activity 3.1: Solving Absolute Value Equations Homework
1. What is the absolute value of a number?
2. Solve or evaluate.
a) |βˆ’7|
b) |7|
c) |4 βˆ’ 9|
3. What are the possible values of x that would satisfy the equation … |π‘₯| = 7 ?
4. Is it possible to have … |π‘₯| = βˆ’2 ?
5. How many solutions are there for absolute value equations?
To Solve Equations with Absolute Value signs:
1. Isolate the Absolute Value
2. Set up 2 Equations – Get rid of the absolute value sign by setting everything in the absolute value equal to a
positive and a negative value.
3. Solve the two equation
Example:
|π‘₯ βˆ’ 2| = 5
(positive)
π‘₯βˆ’2=5
+ 2 +2
x = 7
π‘₯ βˆ’ 2 = βˆ’5
+2 +2
x = –3
(negative)
1
Both π‘₯ = 7 and – 3 are solutions to the equation: |π‘₯ βˆ’ 2| = 5 .
Check your answers by putting them back into the original equation.
|π‘₯ βˆ’ 2| = 5
π‘₯ = βˆ’7 |7 βˆ’ 2| = |5| = 5
π‘₯ = βˆ’3 |βˆ’3 βˆ’ 2| = |βˆ’5| = 5
6. Solve the 2 equations to find the solutions and check:
|π‘₯ βˆ’ 5| + 2 = 9
–2 –2
|π‘₯ βˆ’ 5| = 7
(positive)
π‘₯βˆ’5=7
π‘₯ βˆ’ 5 = βˆ’7
(negative)
Check:
Practice: Please solve and check each absolute value equation.
7. |π‘₯ βˆ’ 3| = 8
Check:
9. |π‘₯ + 1| βˆ’ 7 = 10
Check:
8. |π‘₯ + 4| = 6
Check:
2
10. |π‘₯ βˆ’ 5| + 2 = 4
13. |1 βˆ’ 6𝑛| + 3 = 46
Check:
Check:
11. |2π‘₯ βˆ’ 3| = 5
14
3π‘£βˆ’2
5
=4
Check:
Check:
12. |3π‘₯ βˆ’ 1| + 4 = 9
Check:
3
Part 2: Solve each equation. Be sure to check your solutions by substituting each answer into the original
equation. Make sure you have 2 answers.
a.
xο€­6 ο€½8
Check:
c.
ο€­ 9 x ο€½ 64
Check:
b. x  2 ο€½ ο€­8
Check:
d. ο€­ 7 x  4 ο€½ 18
Check:
4
e. 4 x  4 ο€½ 28
f. 5 n  10 ο€½ 10
Check:
g. 1 ο€­ 6n  3 ο€½ 46
Check:
Check:
h.
3v ο€­ 2
5
ο€½4
Check:
5