SOLUTION: How do you find the point of intersection between y=-1/2x+4 and y=2x+8

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Question 235182: How do you find the point of intersection between y=-1/2x+4 and y=2x+8
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How do you find the point of intersection between
y=-1/2x+4 and y=2x+8
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Substitute for y and solve for "x":
1/2x+4 = 2x+8
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(2x+4)(2x+8) = 1
4(x+2)(x+4) = 1
4(x^2+6x+8) = 1
x^2+6x+8-1/4
x^2+6x+7.75 = 0
---
x = [-6 +- sqrt(36 -4*7.75)]/2
---
x = [-6 +- sqrt(5))/2
---
x = -3 +- 1.118
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x = -4.118 or x = -1.882
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Cheers,
Stan H.