Algebraic

Proofs

What does that mean?

In slightly less math nerd terms

• Addition Property – adding the same value to both sides of the equation

• Subtraction Property – subtracting the same value from both sides of =

• Multiplication Property – multiplying the same value to both sides of =

• Division Property – dividing the same value on both sides of =

In slightly less math nerd terms (con’t)

• Reflexive Property – an value equals itself ex) 4x = 4x

• Symmetric Property – we can write an equation forward or backwards ex) 3x = 8 is the same as 8 = 3x

• Transitive Property – If a = b and b = c then, using the transitive property we can say that a = c ex) ?

• Substitution Property – If x = n (any #), then n can be substituted in for x in any equation or expression ex) all algebra checks

How do I use these terms?

• 3x + 12 = 8x – 18

• ?

• 12 = 5x – 18

• ?

• 30 = 5x

• ?

• 6 = x

• GIVEN

• ? =

• ? =

• ? =

Try this one on your own

• 2x + 4 = 6x – 10

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•

•

• GIVEN

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•

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What do you think of this (solving for r)?

•C = 2πr

•C/2π = r

•GIVEN

• Division Property of Equality

HOMEWORK!

•Worksheet (front and back)

•6 Algebraic Proof Problems – Give Reasons

•Vocab list – IN YOUR OWN WORDS