Big Ideas Ch 3 Expression and Equations

3. 1 Algebraic Expressions

How are they different?

Expression• No =• Can only simplify

Give an Numerical Expression:3 +4

Give an Algebraic Expressions3x+4

Equation• Has an =• Solve for missing variable

Give a Numerical Equation3+4 = 7

Give an Algebraic Equation3x +4 =7

Your brother tries to tell you that 6x +4 -2x is the same thing as 8x+4.

• Is it?• No!!!• Explain why your brother’s answer is

incorrect. • It is incorrect because 6x -2x =4x not 8x • What is the correct answer?• The correct answer is 4x +4• How did you get the correct answer?

Terms

• After you turn all subtraction into addition using (KFC) terms are what is separated by addition signs

Like Terms

• Terms that have the same variables raised to the same exponent

Simplest Form

• Algebraic expressions are in the simplest form when it has not like terms and no parentheses.

Combine Like Terms

• If terms are alike, then you have add or subtract the coefficients (number in front of the variable) and keep the variable to its exponent.

simplify

14- 3z +8 +z14+ (-3z) +8 + 1z-3z +1z +14+8

-2 z +22

Distributive Property

• If there are parentheses and a number on the outside of the () distribute the number through the () then collect like terms

simplify

-2 (g +4) +7g-2(g) +-2(4) +7g

-2g +(-8) +7g-2g +7g +(-8)

5g +(-8)

Simplify3 1

7 4( )4 4x

3 17 4[ ( )]

4 4x

3 17 ( 4)( ) ( 4)( )

4 4x

7 ( 3 ) 1x 3 8x

Homework

• Big Ideas Text Book Page 84 (1-20, 24) all