SOLUTION: I am supposed to solve this simultaneous equation and have tried multiple of times but am not understanding how to do it, it would be nice if you could help. thank you y=x+4 y=

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Question 1163836: I am supposed to solve this simultaneous equation and have tried multiple of times but am not understanding how to do it, it would be nice if you could help. thank you
y=x+4
y= x^2+4x+4
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Imstead of doing it for you, I'll do this one which is
exactly like yours:

y = 3x+7
y = x²+5x+7
Substitute 3x+7 for y in the second equation

3x+7 = x²+5x+7

Get 0 on the left by adding -3x and -7 to both sides:

0 = x²+2x

x²+2x = 0

x(x+2) = 0

x=0, x+2=0
       x=-2

Find y when x=0,   Find y when x=-2

y = 3x+7            y = 3x+7
y = 3(0)+7          y = 3(-2)+7
y = 7               y = -6+7
                    y = 1
There are two solutions:

(x,y) = (-2,7) and (x,y) = (-2,1)

Now use this is as a guide to solve your problem

Edwin