document.write( "Question 79150: I am having trouble solving this system using the substitution method. 2x + y = -1....then underneath x^2 = 4 + y. Thanks for your help! \n" ); document.write( "

Algebra.Com's Answer #56843 by scott8148(6628) $\"\"$ $\"About$

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solving the first equation for y gives y=-1-2x ... substituting into the second equation gives x^2=4-1-2x or x^2+2x-3=0\r
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\n" ); document.write( "\n" ); document.write( "factoring gives (x+3)(x-1)=0 so x=-3 and x=1 ... from the first equation; when x=-3, y=5 and when x=1, y=-3\r
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\n" ); document.write( "\n" ); document.write( "these numbers check with the second equation\r
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