document.write( "Question 553796: When finding a solution of system of equations, for a conic intersection, how do you know what to do when there is a question like \"x%5E2+%2B+y%5E2+=+16\" and x + y = 2? I understand that on the second equation I need to get it to where y = -x - 2, but I dont understand how to plug it into the first equations to find the point. \n" ); document.write( "
Algebra.Com's Answer #361093 by lwsshak3(11628)\"\" \"About 
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When finding a solution of system of equations, for a conic intersection, how do you know what to do when there is a question like x^2 + y^2 = 16 and x + y = 2? I understand that on the second equation I need to get it to where y = -x - 2, but I dont understand how to plug it into the first equations to find the point.
\n" ); document.write( "**
\n" ); document.write( "x + y = 2
\n" ); document.write( "y=2-x
\n" ); document.write( "plug (2-x) for y in second equation
\n" ); document.write( "x^2 + y^2 = 16
\n" ); document.write( "x^2+(2-x)^2=16
\n" ); document.write( "x^2+4-4x+x^2=16
\n" ); document.write( "2x^2-4x-12=0
\n" ); document.write( "x^2-2x-6=0
\n" ); document.write( "Solve by following quadratic formula:
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "a=1, b=-2, c=-6
\n" ); document.write( "x=-(-2)±√[(-2)^2-4*1*(-6)]/2*1
\n" ); document.write( "x=2±√[28]/2
\n" ); document.write( "x=2±5.29/2
\n" ); document.write( "x=3.646
\n" ); document.write( "y=-1.646
\n" ); document.write( "or
\n" ); document.write( "x=-1.646
\n" ); document.write( "y=3.646
\n" ); document.write( ".. \n" ); document.write( "
\n" );