Question

решите уравнение (2a²-5a)+12a-30=0

Answer 1

Ответ:2,5;6
зрсрсһрмрхмзр

Answer 2

$(2 {a}^{2} - 5a) + 12a - 30 = 0 \ 2 {a}^{2} - 5a + 12a - 30 = 0 \ 2 {a}^{2} + 7a - 30 = 0 \ d = b ^{2} - 4ac = {7}^{2} - 4 times 2 times ( - 30) = 49 + 240 = 289 \ a1 = frac{ - b + sqrt{d} }{2a} = frac{ - 7 + sqrt{289} }{2 times 2} = frac{ - 7 + 17}{4} = frac{10}{4} = frac{5}{2} = 2 frac{1}{2} = 2.5 \ a2 = frac{ - b - sqrt{d} }{2a} = frac{ - 7 - 17}{4} = frac{ - 24}{4} = - 6$