Является ли корнем уравнения (х+8)(2х-6)=0 число: 0; -3; 3; -5; 5; -8; 8?

Question

Алгебра: Является ли корнем уравнения (х+8)(2х-6)=0 число: 0; -3; 3; -5; 5; -8; 8?

Мышонок11111 · Accepted Answer

Объяснение:= b2 - 4ac = 92 - 4·2·10 = 81 - 80 = 1

x1 = -9 - √1 2·2 = -9 - 1 4 = -10 4 = -2.5

x2 = -9 + √1 2·2 = -9 + 1 4 = -8 4 = -2

D = b2 - 4ac = 172 - 4·1·0 = 289 - 0 = 289

x1 = -17 - √289 2·1 = -17 - 17 2 = -34 2 = -17

x2 = -17 + √289 2·1 = -17 + 17 2 = 0 2 = 0

D = b2 - 4ac = 82 - 4·5·(-4) = 64 + 80 = 144

x1 = -8 - √144 2·5 = -8 - 12 10 = -20 10 = -2

x2 = -8 + √144 2·5 = -8 + 12 10 = 4 10 = 0.4

D = b2 - 4ac = (-2)2 - 4·7·(-14) = 4 + 392 = 396

x1 = 2 - √396 2·7 = 1 7 - 3 7 √11 ≈ -1.2785534815808857

x2 = 2 + √396 2·7 = 1 7 + 3 7 √11 ≈ 1.5642677672951713

= b2 - 4ac = (-7)2 - 4·1·12 = 49 - 48 = 1

x1 = 7 - √1 2·1 = 7 - 1 2 = 6 2 = 3

x2 = 7 + √1 2·1 = 7 + 1 2 = 8 2 = 4