Combining Like Terms Students will identify like terms and combine like terms to solve problems.

Combine Like Fruits 7 apples 5 bananas + 3 apples + 2 bananas

Only combine terms that are the same!! What’s the “SAME” or “Like Terms” mean? The variables (letters) MUST be the same with the SAME POWERS. You can also combine numbers that have no variables.

Examples Which terms are the “same” or LIKE TERMS? 5x, 8y, 9z, 10, x2, 12x, 14z, 7, 3x2 5x and ? 12x 10 and ? 7 x2 and ? 3x2 8y and ? NOTHING! 9z and ? 14z

Combining Terms To combine Like Terms, add or subtract the coefficients (numbers in front of the variables)… The variable stays the same. Example: 5x + 9x THINK: 5 + 9 = 14 and bring down the x. 14x

Let’s try it! 4x + 9x 13x -7y + 9y 2y -8y + (-4y) -12y 4x + 8y + 10x + 15

More Problems: 4x + 5y – 2x + 3y 5(x + y) + 2(x + y) 3. 3 + 5x – 4y + 2y – 8x 3 + 8y Use the distributive property first. + 7y – 3x – 2y

Problems Cont. 4. (-13) + (-2y) + (-7) – 4y 5. 8(2x – 3y) + 4(y – 3x) -20 5. 8(2x – 3y) + 4(y – 3x) 16x 4x – 6y – 24y + 4y – 12x – 20y

Summary Combine LIKE TERMS only if they have exactly the same letters with the same powers. Combine Like Terms by adding or subtracting the coefficients (numbers) Constants (terms without variables) can also be combined by adding or subtracting. END