№ 542 а) (2x + 3)(3x – 6) = 0; 2x + 3 = 0; 3x – 6 = 0; 2x = – 3; 3x = 6; x = – 1,5; x = 2. Ответ: – 1,5; 2. в) (4a – 8)(6a – 12) = 0; 4a – 8 =0; 6a – 12 = 0; 4a = 8; 6a = 12; a = 2; a = 2. Ответ: 2.
б) (11b + 44)(13b + 26) = 0; 11b + 44 = 0; 13b + 26 = 0; 11b = – 44; 13b = – 26; b = – 4; b = – 2. Ответ: – 4; – 2. г) (25c – 125)(54c – 108) =0; 25c – 125 = 0; 54c – 108 = 0; 25c = 125; 54c = 108; c = 5; c = 2. Ответ: 5; 2.
№ 543 а) m(m + 1)(m + 2) = 0; б) n(n – 3)(n – 8) = 0; m = 0; m + 1 =0; m + 2 =0; n = 0; n – 3 =0; n – 8 =0; m = – 1; m = – 2. n = 3; n = 8. Ответ: – 1; – 2. Ответ: 3; 8. в) p(p + 13)(p – 17) = 0; г) q(q – 21)(q – 105) = 0; p =0; p + 13 = 0; p – 17 = 0; q = 0; q – 21 = 0; q – 105 = 0; p = – 13; p = 17. q = 21; q = 105. Ответ: – 13; 17. Ответ: 21; 105. № 544 а) (4x + 12)(15x + 30)(17x + 34) = 0; 4x + 12 = 0; 15x + 30 = 0; 17x + 34 = 0; 4x = – 12; 15x = – 30; 17x = – 34; x = – 3; x = – 2; x = – 2. Ответ: – 3; – 2. б) (9y + 18)(12y – 48)(36y – 72) = 0; 9y + 18 = 0; 12y – 48 =0; 36y – 72 = 0; y = – 2; y = 4; y =2. Ответ: – 2; 4; 2. в) (23z – 46)(45z + 90)(3z + 24) = 0; 23z – 46 = 0; 45z + 90 = 0; 3z + 24 = 0; z = 2; z = – 2; z = – 8. Ответ: 2; – 2; – 8. г) (4t – 1)(8t – 3)(12t – 17) = 0; 4t – 1 = 0; 8t – 3 = 0; 12t – 17 = 0; 1 3 17 5 ;t= ;t= =1 . 4 8 12 12 1 3 5 Ответ: ; ; 1 . 4 8 12
t=
№ 545 а) x2 – x = 0; x(x – 1) =0; x = 0; x = 1. Ответ: 0; 1. б) 2x2 + 4x = 0; 2x(x + 2) = 0; x = 0; x = – 2. Ответ: 0; – 2. 1 3
1 3
в) 3x2 – 7x = 0; x(3x – 7) = 0; x = 0; x = 2 . Ответ: 0; 2 . г) x2 =4x; x(x – 4) = 0; x = 0; x= 4. Ответ: 0; 4. 88