SOLUTION: Find the solution(s) of each system of equations. y=x^2+6x+9 y=3x

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Question 1137839: Find the solution(s) of each system of equations.
y=x^2+6x+9
y=3x
Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
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Replace y in the first equation by "3x", based on the second equation.


You will get


3x = x^2 + 6x + 9,

x^2 + 3x + 9 = 0,


which has no real solutions, since the discriminant  d = b^2 - 4ac = 3^2 - 4*9 = 9 - 36 = -27 is negative.


The equation has two solutions in complex numbers


x%5B1%2C2%5D = %28-3+%2B-+3%2Asqrt%283%29%2Ai%29%2F2.