document.write( "Question 914436: Given these two equations : f(x)=x^2-6x+9 and g(x)=-3x-5, change the slope of the line so that it will intersect the parabola in two locations.\r
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document.write( "What I have done so far:\r
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document.write( "Let f(x)=g(x)\r
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document.write( "x^2-6x+9=-3x-5
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document.write( "x^2-3x+14=0\r
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document.write( "Then I calculated the discriminant to see how many solutions it would have.\r
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document.write( "D=b^2-4ac
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document.write( "D=(-3)^2-4(1)(14)
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document.write( "D=9-56
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document.write( "D=-47\r
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document.write( "Since the discriminant is -47, therefore there are no real solutions to x^2-3x+14=0, which means that f(x) and g(x) never intersect.\r
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document.write( "What I did for the second part was represent the slope of the second equation with the variable \"m\".\r
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document.write( "f(x)=x^2-6x+9
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document.write( "g(x)=mx-5\r
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document.write( "Let f(x)=g(x)\r
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document.write( "x^2-6x+9=mx-5
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document.write( "x^2-6x-mx+9+5=0
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document.write( "x^2-(6-m)x+14=0\r
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document.write( "a=1, b=-6-m, c=14\r
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document.write( "Sub a, b and c into discriminant equation\r
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document.write( "D=b^2-4ac
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document.write( "D=(-6-m)(-6-m)-4(1)(14)
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document.write( "D=36+6m+6m+m^2-56
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document.write( "D=m^2+12m-20\r
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document.write( "This cannot be factored, so I don't know what to do next!\r
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document.write( "Thanks\r
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document.write( "
Algebra.Com's Answer #555105 by ewatrrr(24785)![]() ![]() You can put this solution on YOUR website! x^2-6x+9=mx-5 Good work \n" ); document.write( "x^2 - 6x - mx + 14 = 0 \n" ); document.write( "x^2 -(6+m)x + 14 = \n" ); document.write( "Re: Discriminant \n" ); document.write( "(6+ m)^2 ≥ 56 \n" ); document.write( "m = 3, for ex: Line would be \n" ); document.write( " (9)^2 ≥ 56 \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "(2,1) and (7,16 ) would be the solutions for this system\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " |