Absolute Value Equations

Solve for x
l 5x l = 40

• x = 8 and x =-8
• x = 35 and x = -35
• Only x = 8
• No Solution

Solve for x
l 2x−1 l = 9

• x = 5 and x =-4
• x = 5 and x = -5
• Only x = 5
• No Solution

Solve for x
l 2x−1 l +4 = 8 

• x = 2.5 and x = -1.5
• x = 2 and x = -1
• x = -2 and x = 9
• No Solution

Solve for x
2 lx−4l+8=18

• x = 9 and x =-1
• x = 1 and x = -9
• x= 4 and x = -2
• No Solution

Evaluate each expression.
| x + 9 | = -5

• -14
• -4
• {-14, -4}
• no solution

What is the reason that absolute value is always written as a positive?

• Absolute value is talking about numbers so it must be positive.
• Absolute value does not always have to be positive.
• Absolute value is like a clock it has only positive numbers.
• Absolute value is talking about distance, distance is always measured by positive numbers.

Solve for x
3 l 4w−1 l −5 = 10

• x = 1.5 and x =-1
• x = -1.5 and x = 1
• x =1 and x = -1
• No Solution

Evaluate each expression.

| x + 9 | = -5

• x = -14

• x = -4

• x = -14 and x = -4}

• no solution

Solve for x.
2|x + 1| - 5 = 5

• x = 4 & x = 6
• x = -4 & x = 6
• x = -6 & x = 4
• no solution

3| −8x| + 8 = 80

• {-7/3, 7/3}
• {-3,3}
• {11/3,-11/3}
• No Solution