Transcript SEC 1.7 LIKE TERMS

SEC 1.7
LIKE TERMS
EXPRESSIONS WITH THE
SAME VARIABLE AND SAME
EXPONENT
EXAMPLES
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LIKE TERMS
3x + 5x
3y + 5y
3x2 + 5x2
3xy + 5xy
3x2y + 5x2y
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UNLIKE TERMS
3x + 5
3x + 5y
3x2 + 5x
3xy + 5x
3x2y + 5xy2
TO ADD LIKE TERMS
• Add the coefficients
• Place the variable(s) behind the
coefficient
• Leave the exponents alone
• Expressions written in alphabetical
order
• Expressions written in descending
order of exponents
• Constant term is always written last
EXAMPLES
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SIMPLIFY
3x + 5x
3y + 5y
3x2 + 5x2
3xy + 5xy
3x2y + 5x2y
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ANSWER
8x
8y
8x2
8xy
8x2y
THINGS TO REMEMBER
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x = 1x (Multiplicative Identity Property)
-x = -1 x (Multiplication Property of -1)
-(-6) = 6
+(-6) = -6
 -(-6x) = 6x
+(-6x) = -6x
EXAMPLE #1
4x - 6 + (-9x) – (-3) – (-7x) + (-5)
4x – 6 – 9x + 3 + 7x – 5
4x – 9x + 7x – 6 + 3 – 5
4x + 7x – 9x – 6 – 5 + 3
11x – 9x – 11 + 3
2x - 8
EXAMPLE #2
5x – 6y + (-8x) – (-7) – (-4x) + (-8y) - 2
5x – 6y – 8x + 7 + 4x – 8y - 2
5x – 8x + 4x – 6y – 8y + 7 - 2
5x + 4x – 8x – 6y – 8y + 7 - 2
9x – 8x – 14y + 7 - 2
x – 14y + 5
EXAMPLE #3
-x2 – 6x - (-8x) – (-5x2) – (-4) + (-7x) + (-12)
-x2 – 6x + 8x + 5x2 + 4 – 7x - 12
-x2 + 5x2 – 6x + 8x – 7x + 4 - 12
-x2 + 5x2 – 6x – 7x + 8x + 4 - 12
4x2 – 13x + 8x - 8
4x2 – 5x - 8