3. Factor the trinomial. Verify that the factors are correct. 30c3d2 25cd –20c4d – – Solution 30c3d2 25cd –20c4d – – Factor each term of the trinomial. 20c4d = 2 · 2 · 5 · · · · · c c c c d 30c3d2 = 2 · 3 · 5 · · · · · c c c d d 25cd = 5 · 5 · · c d The greatest common factor is 5 · · = 5cd c d each term as a product of the greatest common factor and another monomial. 30c3d2 25cd –20c4d – – = 5cd(–4c3) 5cd(6c2d) 5cd(5) Write the expression as a product. – – = 5cd(–4c3 6c2d 5) – – = 5cd(–1)(4c3 + 6c2d + 5) = + 6c2d + 5) –5cd(4c3 Check: Expand + 6c2d + 5) –5cd(4c3 = (–5cd)(4c3) + (–5cd)(6c2d) + (–5cd)(5) = 30c3d2 25cd –20c4d – – This trinomial is the same as the original trinomial, so the factors are correct. Homework read page150-154 Do pg 155 #5,6 #7-10 ignore algebra tiles #14, 16 ,17 # 22
3. Factor the trinomial. Verify that the factors are correct. –20c4d – 30c3d2 – 25cd Solution –20c4d – 30c3d2 – 25cd Factor each term of the trinomial. 20c4d = 2 · 2 · 5 · c · c · c · c · d 30c3d2 = 2 · 3 · 5 · c · c · c · d · d 25cd = 5 · 5 · c · d The greatest common factor is 5 · c · d = 5cd each term as a product of the greatest common factor and another monomial. –20c4d – 30c3d2 – 25cd = 5cd(–4c3) – 5cd(6c2d) – 5cd(5) Write the expression as a product. = 5cd(–4c3 – 6c2d – 5) = 5cd(–1)(4c3 + 6c2d + 5) = –5cd(4c3 + 6c2d + 5) Check: Expand –5cd(4c3 + 6c2d + 5) = (–5cd)(4c3) + (–5cd)(6c2d) + (–5cd)(5) = –20c4d – 30c3d2 – 25cd This trinomial is the same as the original trinomial, so the factors are correct. Homework read page150-154 Do pg 155 #5,6 #7-10 ignore algebra tiles #14, 16 ,17 # 22