4. Factor. 20h + 60 –5h2 – Solution 20h + 60 –5h2 – The greatest common factor is 5. Since the coefficient of the first term is negative, use as the common factor. –5 20h + 60 = + 4h 12) –5h2 – –5(h2 – Two numbers with a sum of 4 and a product of are and 6. –12 –2 So, + 4h 12 = (h 2)(h + 6) h2 – – And, 20h + 60 = 2)(h + 6) –5h2 – –5(h – Since factoring and expanding are inverse processes, check that the factors are correct. Multiply the factors. 2)(h + 6) = + 4h 12) –5(h – –5(h2 – = 20h + 60 –5h2 – This trinomial is the same as the original trinomial, so the factors are correct. Homework read page 159-165 Do page 166 #7 #9, 10, 11, 12, 14, 15, 21 #23 Ignore tiles and sketches
4. Factor. –5h2 – 20h + 60 Solution –5h2 – 20h + 60 The greatest common factor is 5. Since the coefficient of the first term is negative, use –5 as the common factor. –5h2 – 20h + 60 = –5(h2 + 4h – 12) Two numbers with a sum of 4 and a product of –12 are –2 and 6. So, h2 + 4h – 12 = (h – 2)(h + 6) And, –5h2 – 20h + 60 = –5(h – 2)(h + 6) Since factoring and expanding are inverse processes, check that the factors are correct. Multiply the factors. –5(h – 2)(h + 6) = –5(h2 + 4h – 12) = –5h2 – 20h + 60 This trinomial is the same as the original trinomial, so the factors are correct. Homework read page 159-165 Do page 166 #7 #9, 10, 11, 12, 14, 15, 21 #23 Ignore tiles and sketches
miap_ch3_notes.docx