document.write( "Question 955425: y=x^2/16+21x/16+11/8 the equation is x^2 devided by16 + 21x devided by 16
\n" ); document.write( " + 11 devided by 8\r
\n" ); document.write( "\n" ); document.write( "s a parabola.\r
\n" ); document.write( "\n" ); document.write( "(i) Is the parabola u-shaped or n-shaped? How can you tell this from\r
\n" ); document.write( "\n" ); document.write( "the equation? [1]\r
\n" ); document.write( "\n" ); document.write( "(ii) Use algebra to find the x-intercepts. [4]\r
\n" ); document.write( "\n" ); document.write( "(iii) Explain why the y-intercept is 11/8\r
\n" ); document.write( "\n" ); document.write( "(iv) Find the equation of the axis of symmetry, explaining your\r
\n" ); document.write( "\n" ); document.write( "method. Use this information to find the coordinates of the\r
\n" ); document.write( "\n" ); document.write( "vertex, rounding your answers where necessary to one decima i think the parabol is u shaped due to their being a negative number in the equation. i think the 2nd answer is y=x^2/16+21x/16+11/8 16y=x^2+21x+22 \r
\n" ); document.write( "\n" ); document.write( "16y-x^2-21x-22=0 ax^2+bx+c=0 a=-1, b=-21, c=-22+16y\r
\n" ); document.write( "\n" ); document.write( "x=21 sqrt64y+353/-2 21-sqrt 64y+353/-2 simplyfy \r
\n" ); document.write( "\n" ); document.write( "x=21+sqrt 64y+353/2 - 21-sqrt 64y+353/2''.\r
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Algebra.Com's Answer #583701 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\"y=x%5E2%2F16%2B21x%2F16%2B11%2F8+\"\r
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\n" ); document.write( "\n" ); document.write( "(i) Is the parabola u-shaped or n-shaped? How can you tell this from\r
\n" ); document.write( "\n" ); document.write( "the equation? \r
\n" ); document.write( "\n" ); document.write( "the parabola is u-shaped, \"a=1%2F16\" and \"a%3E0\"
\n" ); document.write( " \r
\n" ); document.write( "\n" ); document.write( "(ii) Use algebra to find the x-intercepts. \r
\n" ); document.write( "\n" ); document.write( "\"y=x%5E2%2F16%2B21x%2F16%2B11%2F8+\".... x-intercepts occur where \"y+=+0\", so we have\r
\n" ); document.write( "\n" ); document.write( "\"0=x%5E2%2F16%2B21x%2F16%2B11%2F8+\"....both sides multiply by \"16\"\r
\n" ); document.write( "\n" ); document.write( "\"0%2A16=16x%5E2%2F16%2B%2816%2A21x%29%2F16%2B%2816%2A11%29%2F8+\"\r
\n" ); document.write( "\n" ); document.write( "\"0=x%5E2%2B21x%2B2%2A11+\"\r
\n" ); document.write( "\n" ); document.write( "\"0=x%5E2%2B21x%2B22+\"....use quadratic formula\r
\n" ); document.write( "\n" ); document.write( "\"x+=+%28-21+%2B-+sqrt%28+21%5E2-4%2A1%2A22+%29%29%2F%282%2A1%29+\" \r
\n" ); document.write( "\n" ); document.write( "\"x+=+%28-21+%2B-+sqrt%28+441-88+%29%29%2F2+\"\r
\n" ); document.write( "\n" ); document.write( "\"x+=+%28-21+%2B-+sqrt%28+353+%29%29%2F2+\".........exact solutions\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-21+%2B-+18.79%29%2F2+\"\r
\n" ); document.write( "\n" ); document.write( "approximate solutions:\r
\n" ); document.write( "\n" ); document.write( "\"x+=+%28-21+%2B+18.79%29%2F2+\"\r
\n" ); document.write( "\n" ); document.write( "\"x+=-1.11\"\r
\n" ); document.write( "\n" ); document.write( "or\r
\n" ); document.write( "\n" ); document.write( "\"x+=+%28-21+-+18.79%29%2F2+\"\r
\n" ); document.write( "\n" ); document.write( "\"x+=-19.9\"\r
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\n" ); document.write( "\n" ); document.write( "(iii) Explain why the y-intercept is \"11%2F8\"\r
\n" ); document.write( "\n" ); document.write( "y-intercept occurs where \"x+=+0\", yielding (\"0\",\"11%2F8\")
\n" ); document.write( "\"y=0%5E2%2F16%2B21%2A0%2F16%2B11%2F8+\"\r
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\n" ); document.write( "\n" ); document.write( "(iv) Find the equation of the axis of symmetry, explaining your\r
\n" ); document.write( "\n" ); document.write( "method. Use this information to find the coordinates of the\r
\n" ); document.write( "\n" ); document.write( "vertex, rounding your answers where necessary to one decimal\r
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\n" ); document.write( "\n" ); document.write( "The axis of symmetry is \"x+=+-b%2F2a\". Since \"a=1%2F16\" and \"b=21%2F16\"\r
\n" ); document.write( "\n" ); document.write( "\"x+=+-%2821%2F16%29%2F%282%281%2F16%29%29\"\r
\n" ); document.write( "\n" ); document.write( "\"x+=+-%2821%2Fcross%2816%29%29%2F%282%2Fcross%2816%29%29%29\"\r
\n" ); document.write( "\n" ); document.write( "\"x+=+-%2821%2F2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"x+=+-10.5\"\r
\n" ); document.write( "\n" ); document.write( " That is also x-coordinate of the vertex, plug it in \"y=x%5E2%2F16%2B21x%2F16%2B11%2F8+\" and find y-coordinate
\n" ); document.write( "\"y=%28-10.5%29%5E2%2F16%2B21%2A%28-10.5%29%2F16%2B11%2F8+\"
\n" ); document.write( "\"y=-5.5\"\r
\n" ); document.write( "\n" ); document.write( "the vertex is at: (\"-10.5\",\"-5.5\")\r
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