x - x2 - 9x + 14 = 0 ; whence, x2 + 8x = 14 , x2 + 8x + 16 = 30 , and x + 4 = ±√30 . Therefore, x = ±√30 - 4 .
-18
x2 - x = 20 x2 - x - 20 = 0 (x - 5)(x + 4) = 0 x - 5 = 0 and x + 4 = 0 So, x = 5 ans x = -4
x2 - 9x - 6 = 0 x2 - 9x + (9/2)2 = 6 + (9/2)2 (x - 9/2)2 = 6 + 81/4 x - 9/2 = ± √105 / 2 x = (9 ± √105) / 2
x3=x2 x3-x2=0 Factor out x2 x2(x - 1) = 0 If x2=0 then x=0. If x - 1 = 0 then x = 1. Therefore the number is 0 or 1.
2x - 81 = 0 Add 81 to both sides. 2x - 81 + 81 = 0 + 81 Substitute, -81 + 81 cancels out. 2x = 81 Divide by 2. x = 40.5 Above answer would be correct if your question was 2x but it was x2 so using the same method you would get x2 = 81 here the opposite of the square is the square root x = 9
144X = X2 144X - X2 = 0 (144 - X)X = 0 X = 0 or X = 144
x2 + 6x + 9 = 81 x2 + 6x = 72 x2 + 6x - 72 = 0 (x+12)(x-6) = 0 x= -12, 6 (two solutions)
x2 plus 3x plus 3 is equals to 0 can be solved by getting the roots.
x2-2x-3 = 0 (x+1)(x-3) = 0 x = -1 or x = 3
Divide all terms by 3:- x2-12+27 = 0 When factored:- (x-3)(x-9) = 0 Therefore: x = 3 or x = 9
x2 + 13x = -30 ∴ x2 + 13x + 30 = 0 ∴ (x + 3)(x + 10) = 0 ∴ x ∈ {-3, -10}
x2 + 4x + 3 = 0 (x + 1)(x + 3) = 0 x ∈ {-3, -1}
x2 + 7x = 0 => x*(x + 7) = 0 => x = 0 or x + 7 = 0 so that x = 0 or x = -7
To solve for x: x2 = 11x - 10 x2 - 11x = -10 x2 - 11x + 10 =0 (x - 1)(x - 10) = 0 x = {1, 10)
x2-4x-21 = 0 => x = -3 or x = 7 x2-3x-18 = 0 => x = -3 or x = 6
x2 - 9x = -8 ∴ x2 - 9x + 8 = 0 ∴ (x - 1)(x - 8) = 0 You can then solve it as well: ∴ x ∈ {1, 8}