1 Absolute Value A1

Evaluate

| –12 | – | 8 |

• 4

• -4

• 30

• -20

| –3 |

• 3

• -3

• 0.30

• 30

What's a way to define absolute value?

• The value of a number

• The opposite of a number

• The distance of a number from zero

• The multiplicative inverse of a number

What is the absolute value of |572|.

• 275

• -572

• 57

• 572

Choose the inequality that makes this true:

∣-5∣ _____ ∣5∣

• <

• >

• =

The absolute value of zero is zero because...

• Zero is not a number.

• Zero is 0 distance from zero.  It is neither negative or positive.

Solve for x
l 5x l = 40

• x = 8 and x =-8

• x = 35 and x = -35

• Only x = 8

• No Solution

Why does this equation have NO SOLUTION?

l 2x−1 l =- 9

• Because of the -1

• Because the absolute value of an expression can never equal a negative

• Because x can not be isolated

• Because 9 divided by 2 is a fraction

Solve for x
l 4x−3 l = 17

• x = 5 and x =-3.5

• x = 0 and x = -5

• x = 10 and x = -10

• No Solution

What is the first step?

|v + 8| − 5 = 2

• Add 5 to both sides

• Make 2 equations, one equal to 2 and the other equal to -2

• Subtract 8

• Subtract 2 from both sides