document.write( "Question 155165: 1. Determine whether the following equations have a solution or not? Justify your answer. \r
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\n" ); document.write( "\n" ); document.write( "a) x^2 + 6x - 7 = 0
\n" ); document.write( "b) z^2 + z + 1 = 0
\n" ); document.write( "c) (3)^(1/2)*y^2 - 4y - 7*(3)^(1/2) = 0
\n" ); document.write( "d) 2x^2 - 10x + 25 = 0
\n" ); document.write( "e) 2x^2 - 6x + 5 = 0
\n" ); document.write( "f) s^2 - 4s + 4 = 0
\n" ); document.write( "g) (5/6)x^2 - 7x - 6/5 = 0
\n" ); document.write( "h) 7a^2 + 8a + 2 = 0
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Algebra.Com's Answer #114233 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
a)\r
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\n" ); document.write( "\n" ); document.write( "From \"x%5E2%2B6x-7\" we can see that \"a=1\", \"b=6\", and \"c=-7\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=b%5E2-4ac\" Start with the discriminant formula.\r
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\n" ); document.write( "\n" ); document.write( "\"D=%286%29%5E2-4%281%29%28-7%29\" Plug in \"a=1\", \"b=6\", and \"c=-7\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=36-4%281%29%28-7%29\" Square \"6\" to get \"36\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=36--28\" Multiply \"4%281%29%28-7%29\" to get \"%284%29%28-7%29=-28\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=36%2B28\" Rewrite \"D=36--28\" as \"D=36%2B28\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=64\" Add \"36\" to \"28\" to get \"64\"\r
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\n" ); document.write( "\n" ); document.write( "Since the discriminant is greater than zero, this means that there are two real solutions.\r
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\n" ); document.write( "\n" ); document.write( "From \"z%5E2%2Bz%2B1\" we can see that \"a=1\", \"b=1\", and \"c=1\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=b%5E2-4ac\" Start with the discriminant formula.\r
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\n" ); document.write( "\n" ); document.write( "\"D=%281%29%5E2-4%281%29%281%29\" Plug in \"a=1\", \"b=1\", and \"c=1\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=1-4%281%29%281%29\" Square \"1\" to get \"1\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=1-4\" Multiply \"4%281%29%281%29\" to get \"%284%29%281%29=4\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=-3\" Subtract \"4\" from \"1\" to get \"-3\"\r
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\n" ); document.write( "\n" ); document.write( "Since the discriminant is less than zero, this means that there are two complex solutions. In other words, there are no real solutions.\r
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\n" ); document.write( "\n" ); document.write( "c)\r
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\n" ); document.write( "\n" ); document.write( " Start with the given expression\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%283%29y%5E2-4y-7%2Asqrt%283%29\" Rewrite as \"sqrt%283%29\"\r
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\n" ); document.write( "\n" ); document.write( "From \"sqrt%283%29y%5E2-4y-7%2Asqrt%283%29\", we can see that \"a=sqrt%283%29\", \"b=-4\", and \"c=7%2Asqrt%283%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=b%5E2-4ac\" Start with the discriminant formula\r
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\n" ); document.write( "\n" ); document.write( "\"Photobucket\r
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\n" ); document.write( "\n" ); document.write( "\"D=100\" Add\r
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\n" ); document.write( "\n" ); document.write( "Since the discriminant is greater than zero, this means that there are two real solutions.\r
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\n" ); document.write( "\n" ); document.write( "From \"2x%5E2-10x%2B25\" we can see that \"a=2\", \"b=-10\", and \"c=25\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=b%5E2-4ac\" Start with the discriminant formula.\r
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\n" ); document.write( "\n" ); document.write( "\"D=%28-10%29%5E2-4%282%29%2825%29\" Plug in \"a=2\", \"b=-10\", and \"c=25\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=100-4%282%29%2825%29\" Square \"-10\" to get \"100\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=100-200\" Multiply \"4%282%29%2825%29\" to get \"%288%29%2825%29=200\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=-100\" Subtract \"200\" from \"100\" to get \"-100\"\r
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\n" ); document.write( "\n" ); document.write( "Since the discriminant is less than zero, this means that there are two complex solutions. In other words, there are no real solutions.\r
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\n" ); document.write( "\n" ); document.write( "e)\r
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\n" ); document.write( "\n" ); document.write( "From \"2x%5E2-6x%2B5\" we can see that \"a=2\", \"b=-6\", and \"c=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=b%5E2-4ac\" Start with the discriminant formula.\r
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\n" ); document.write( "\n" ); document.write( "\"D=%28-6%29%5E2-4%282%29%285%29\" Plug in \"a=2\", \"b=-6\", and \"c=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=36-4%282%29%285%29\" Square \"-6\" to get \"36\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=36-40\" Multiply \"4%282%29%285%29\" to get \"%288%29%285%29=40\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=-4\" Subtract \"40\" from \"36\" to get \"-4\"\r
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\n" ); document.write( "\n" ); document.write( "Since the discriminant is less than zero, this means that there are two complex solutions. In other words, there are no real solutions.\r
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\n" ); document.write( "\n" ); document.write( "f)\r
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\n" ); document.write( "\n" ); document.write( "From \"s%5E2-4s%2B4\" we can see that \"a=1\", \"b=-4\", and \"c=4\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=b%5E2-4ac\" Start with the discriminant formula.\r
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\n" ); document.write( "\n" ); document.write( "\"D=%28-4%29%5E2-4%281%29%284%29\" Plug in \"a=1\", \"b=-4\", and \"c=4\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=16-4%281%29%284%29\" Square \"-4\" to get \"16\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=16-16\" Multiply \"4%281%29%284%29\" to get \"%284%29%284%29=16\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=0\" Subtract \"16\" from \"16\" to get \"0\"\r
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\n" ); document.write( "\n" ); document.write( "Since the discriminant is equal to zero, this means that there is one real solution.\r
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\n" ); document.write( "\n" ); document.write( "g)\r
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\n" ); document.write( "\n" ); document.write( "From \"%285%2F6%29x%5E2-7x-%286%2F5%29\" we can see that \"a=5%2F6\", \"b=-7\", and \"c=-6%2F5\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=b%5E2-4ac\" Start with the discriminant formula.\r
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\n" ); document.write( "\n" ); document.write( "\"D=%28-7%29%5E2-4%285%2F6%29%28-6%2F5%29\" Plug in \"a=5%2F6\", \"b=-7\", and \"c=-6%2F5\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=49-4%285%2F6%29%28-6%2F5%29\" Square \"-7\" to get \"49\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=49--4\" Multiply \"4%285%2F6%29%28-6%2F5%29\" to get \"%2810%2F3%29%28-6%2F5%29=-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=49%2B4\" Rewrite \"D=49--4\" as \"D=49%2B4\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=53\" Add \"49\" to \"4\" to get \"53\"\r
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\n" ); document.write( "\n" ); document.write( "Since the discriminant is greater than zero, this means that there are two real solutions.\r
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\n" ); document.write( "\n" ); document.write( "From \"7a%5E2%2B8a%2B2\" we can see that \"a=7\", \"b=8\", and \"c=2\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=b%5E2-4ac\" Start with the discriminant formula.\r
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\n" ); document.write( "\n" ); document.write( "\"D=%288%29%5E2-4%287%29%282%29\" Plug in \"a=7\", \"b=8\", and \"c=2\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=64-4%287%29%282%29\" Square \"8\" to get \"64\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=64-56\" Multiply \"4%287%29%282%29\" to get \"%2828%29%282%29=56\"\r
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\n" ); document.write( "\n" ); document.write( "\"D=8\" Subtract \"56\" from \"64\" to get \"8\"\r
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\n" ); document.write( "\n" ); document.write( "Since the discriminant is greater than zero, this means that there are two real solutions.\r
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