Question

Решить уравнения .Очень надо
1....3х-х-2=0
2....4х²+х-5=0
3...(x-6)²=(7-x)
4...x-4(9-x)=3x+2
5...-5x+9(-1+2x)=9x-1
6...4x²+6x-2=(x-1)²
7...2x²+11x+34=(x+6)²

Answer 1

1) 2x - 2 = 0
2x = 2
x = 2/2
x = 1
2) 4x² + x - 5 = 0
D = b² - 4ac = 1² - 4 × 4 × ( - 5) = 1 + 80 = 81 = 9²
x₁ = (- 1 + 9)/ 8 =1
x₂ (-1 - 9)/8= - 10/8 = -1,25
3) (x- 6)(x - 6) = 7 - x
x² - 12x + 36 - 7 + x =0
x² - 11x + 29 = 0
D = b² - 4ac = (-11)² - 4 × 1 × 29 = 121 - 116 = 5
x₁,₂ = 11⁺/⁻√5 / 2
4) x- 36 + 4x = 3x + 2
5x - 3x = 36 + 2
2x = 38
x = 38/2
x = 19
5) - 5x - 9 + 18x = 9x - 1
13x - 9x = 9 - 1
4x = 8
x = 8/4
x = 2
6) 4x² + 6x - 2 = (x - 1)(x - 1)
4x² + 6x - 2 = x² - 2x + 1
4x² + 6x - 2 - x² + 2x - 1 = 0
3x² + 8x - 3 = 0
D = b² - 4ac = 8² - 4 × 3 × (-3) = 64 + 36 = 100 = 10²
x₁ = (- 8 + 10 )/ 6 =2/6 = 1/3
x₂ = (-8 - 10) / 6 = - 18/6 = - 3
7) 2x² + 11x + 34 = ( x + 6)(x + 6)
2x² + 11x + 34 = x² + 12x + 36
2x² + 11x + 34 - x² - 12x - 36 = 0
x² - x - 2 = 0
D = b² - 4ac = (-1)² - 4 × 1 × ( - 2) = 1 + 8 =9 = 3²
x₁ = (1 + 3) / 2 = 2
x₂ = (1 - 3) / 2 = - 2/2 = - 1