SOLUTION: Find the solution to the system y=xsquared+5 and y=2x+4 thank you

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Question 24619: Find the solution to the system y=xsquared+5 and y=2x+4
thank you
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
y=x%5E2+%2B+5
y+=+2x+%2B+4

Therefore
y=y
x%5E2+%2B5+=+2x+%2B+4, which is a quadratic equation. Solve by setting it equal to zero:
x%5E2+%2B+5+-+2x+-+4=+0
x%5E2+-2x+%2B+1+=+0
%28x-1%29%5E2+=+0
x=1

Substitute back into either equation, usually the simplest one is best!
y = 2x +4
y = 2(1) + 4
y = 6

There is only one point of intersection, (1, 6) .

Just for fun, let's check by graphing:
graph+%28400%2C400%2C+-10%2C10%2C-10%2C10%2C+x%5E2%2B5%2C+2x%2B4%29

R^2 at SCC