x2 + 7x + 9 = 3 ∴ x2 + 7x + 6 = 0 ∴ (x + 6)(x + 1) = 0 ∴ x ∈ {-6, -1}
If: x+3+6x+9 = 0 then 7x+12 = 0 So: 7x = -12 and x = -12/7
7x + y + z = 6 7x + y + 4z = 9 y + x = 6 Take the first two statements and subtract them. 7x + y + z = 6 7x + y + 4z = 9 _____________ 0 + 0 - 3z = -3 Therefore: z = 1 Then you are left with: 7x + y + 1 = 6 7x + y + 4 = 9 which is impossible, so this is an impossible equation.
-7x + 5 = -9 -7x = -14 7x = 14 x = 2
x=4 x=0
x2+11x+11 = 7x+9 x2+11x-7x+11-9 = 0 x2+4x+2 = 0 The above quadratic equation can be solved by using the quadratic equation formula and it will have two solutions.
4x+9 = 7x+3 4x-7x = 3-9 -3x = -6 x = 2
X2+11x+11 = 7x+9 X2+11x-7x+11-9 = 0 x2+4x+2 = 0 Solve as a quadratic equation by using the quadratic equation formula or by completing the square: x = -2 + or - the square root of 2
Subtract 7x from each side: 8 = -9 Not possible, game over.
answer is 4 7x+19=-2x+55 +2x +2x 9x+19= 0 55 -19 -19 9x = 36 9 9 =4
8x-2 = -9+7x8x-7x = -9+2x=-7
7x + 9 = 51 7x = 42 x = 42/7 = 6