 # 8.5 Warm-up 3.4. 5. 6.. 8-5 Add and Subtract Rational Expressions Adding and Subtracting with Like Denominators 1.2.3.

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8.5 Warm-up 3.4. 5. 6.

8-5 Add and Subtract Rational Expressions Adding and Subtracting with Like Denominators 1.2.3.

Find the LCM 1. 5x 2 – 45 and 4x 2 + 24x + 36 5(x 2 – 9) = 5(x – 3)(x + 3) 4x 2 + 24x + 36 = 4(x 2 + 6x + 9) = 4(x + 3)(x + 3) = 4(x + 3) 2 LCM is 20(x – 3)(x + 3) 2 2. 5x 3 and 10x 2 – 15x 5x 3 5x(2x – 3) LCM is 5x 3 (2x - 3) Step 1 – Factor each polynomial. Write the factors as products of primes. Step 2 – Form the LCM by writing each factor to the highest power it occurs.

Find the LCM 3. 24x 2 and 8x 2 – 16x (2 3 )(3)x 2 8x(x – 2) = (2 3 )x(x-2) LCM is 24x 2 (x – 2) Add and Subtract with Unlike Denominators 4. LCM is 10c 2 (c - 2)

5. LCM is 30x 6. LCM is 2(x – 1)(x – 3)

7. LCM is (x + 2)(x + 2)(x – 2)

Simplifying Complex Fractions 8. LCM is 30 9. LCM is x

Homework: Page 586: 3 -36 10. LCM is (x – 3)(x + 5)