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x² + 2x − 15 = 0

x₁ = −5; x₂ = 3

x² − 5x − 14 = 0

x₁ = −2; x₂ = 7

x² − 7x + 6 = 0

x₁ = 1; x₂ = 6

x² + 14x + 40 = 0

x₁ = −4; x₂ = −10

x² + 4x − 45 = 0

x₁ = 5; x₂ = −9

x² + 5x − 24 = 0

x₁ = 3; x₂ = −8

x² − 3x − 54 = 0

x₁ = 9; x₂ = −6

x² − 13x + 22 = 0

x₁ = 11; x₂ = 2

x² − 13x = 0

x₁ = 0; x₂ = 13

x² − 22x + 85 = 0

x₁ = 17; x₂ = 5

x² + x − 42 = 0

x₁ = 6; x₂ = −7

2x² − 2x − 24 = 0

x₁ = 4; x₂ = −3

2x² − 20x − 150 = 0

x₁ = 15; x₂ = −5

x² + x − 156 = 0

x₁ = 12; x₂ = −13

x² + 10x + 9 = 0

x₁ = −1; x₂ = −9

x² = 1,5x + 7

x₁ = −2; x₂ = 3,5

x² − x = 92⋅(1 − x)

x₁ = −92; x₂ = 1

3x² − 25x = 50

x₁ = 10; x₂ = −5/3

−9x² + 7 = 28x

x₁ = 1/4; x₂ = −7/3

2x² − 2x = 12

x₁ = 3; x₂ = −2

x² + 4x = −3,75

x₁ = −1,5; x₂ = −2,5

2x² + 8x = −7,5

x₁ = −1,5; x₂ = −2,5

x² = 88−3x

x₁ = 8; x₂ = −11

20x² − 40x = 60

x₃ = 0; x₂ = −1

3x² + 9x = 0

x₁ = 0; x₂ = −3

50x² + 5x = 6

x₁ = −2/5; x₂ = 3/10

x² + 0,95x = 1,4

x₁ = −7/4; x₂ = 4/5

2x² + x/2 = 3/32

x₁ = −1/4; x₂ = 3/8

−4x² + 0,4x = −9,6

x₁ = −1,5; x₂ = 1,6

6x² − 51x = −105

x₁ = 5; x₂ = 3,5

1,2x² + 7,8x = 14,4

x₁ = −8; x₂ = 1,5

20,4x² + 30,6x = 20,4

x₁ = −2; x₂ = 0,5