document.write( "Question 623928: I need someone help i am stuck doing this last part of my homework. can someone explain it to me \r
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document.write( "Match each equation for a parabola with the direction that the parabola opens.\r
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document.write( "1. y=-3(x+1)^2-8
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document.write( "2. x=-3(y+1)^2-8
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document.write( "3. y=3(x+1)^2-8
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document.write( "4. x=3(y+1)^2-8\r
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document.write( "A. up
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document.write( "B. right
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document.write( "C. down
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document.write( "D. left \r
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Algebra.Com's Answer #392414 by Theo(13342)![]() ![]() You can put this solution on YOUR website! if y = x^2, then the parabola will open up. \n" ); document.write( "if y = -x^2, then the parabole will open down. \n" ); document.write( "if x = y^2, then the parabola will open to the right. \n" ); document.write( "if x = -y^2, then the parabole will open to the left. \n" ); document.write( "what we are dealing with is the coefficient of the squared term. \n" ); document.write( "your equations are: \n" ); document.write( "1. y=-3(x+1)^2-8 \n" ); document.write( "2. x=-3(y+1)^2-8 \n" ); document.write( "3. y=3(x+1)^2-8 \n" ); document.write( "4. x=3(y+1)^2-8 \n" ); document.write( "(x+1)^2 will be equal to x^2 + 2x + 1 \n" ); document.write( "(y+1)^2 will be equal to y^2 + 2y + 1 \n" ); document.write( "your equations therefore become: \n" ); document.write( "1. y = -3(x^2 + 2x + 1) - 8 \n" ); document.write( "2. x = -3(y^2 + 2y + 1) - 8 \n" ); document.write( "3. y = 3(x^2 + 2x + 1) - 8 \n" ); document.write( "4. x = 3(y^2 + 2y + 1) - 8 \n" ); document.write( "remove parentheses and simplify to get: \n" ); document.write( "1. y = -3x^2 - 6x - 11 \n" ); document.write( "2. x = -3y^2 - 6y - 11 \n" ); document.write( "3. y = 3x^2 + 6x - 5 \n" ); document.write( "4. x = 3y^2 + 3y - 5 \n" ); document.write( "when determining whether the parabole will open up or down, the only meaningful consideration is the sign of the coefficient of the squared term. \n" ); document.write( "based on this, you should get the following answers. \n" ); document.write( "1. will open down \n" ); document.write( "2. will open to the left. \n" ); document.write( "3. will open up. \n" ); document.write( "4. will open to the right. \n" ); document.write( "we can graph these equations and see how we did. \n" ); document.write( "to graph these equations, you have to solve for y in all equations. \n" ); document.write( "the original equations are: \n" ); document.write( "1. y=-3(x+1)^2-8 \n" ); document.write( "2. x=-3(y+1)^2-8 \n" ); document.write( "3. y=3(x+1)^2-8 \n" ); document.write( "4. x=3(y+1)^2-8 \n" ); document.write( "equations 1 and 3 can be graphed as is. \n" ); document.write( "you need to solve for y in equations 2 and 4. \n" ); document.write( "equation 2 is: \n" ); document.write( "x = -3(y+1)^2 - 8 \n" ); document.write( "add 3(y+1)^2 to both sides of this equation and subtract x from both sides of this equation to get: \n" ); document.write( "3(y+1)^2 = -x - 8 \n" ); document.write( "divide both sides of this equation by 3 to get: \n" ); document.write( "(y+1)^2 = (-x-8)/3 which is the same as: \n" ); document.write( "(y+1)^2 = -(x+8)/3 \n" ); document.write( "take the square root of both sides of this equation to get: \n" ); document.write( "y+1 = +/- ( -(x+8)/3 ) \n" ); document.write( "subtract 1 from both sides of this equation to get: \n" ); document.write( "y = -1 +/- sqrt( -(x+8)/3 ) \n" ); document.write( "equations to graph for equation 2 are: \n" ); document.write( "y = -1 + sqrt( -(x+8)/3 ) \n" ); document.write( "y = -1 - sqrt( -(x+8)/3 ) \n" ); document.write( "equation 4 is: \n" ); document.write( "x = 3(y+1)^2 - 8 \n" ); document.write( "add 8 to both sides of this equation to get: \n" ); document.write( "3(y+1)^2 = x + 8 \n" ); document.write( "divide both sides of this equation by 3 to get: \n" ); document.write( "(y+1)^2 = (x+8)/3 \n" ); document.write( "take the square root of both sides of this equation to get: \n" ); document.write( "y+1 = +/- sqrt( (x+8)/3 ) \n" ); document.write( "subtract 1 from both sides of this equation to get: \n" ); document.write( "y = -1 +/- sqrt( (x+8)/3 ) \n" ); document.write( "equations to graph for equation 4 are: \n" ); document.write( "y = -1 + sqrt( (x+8)/3 ) \n" ); document.write( "y = -1 - sqrt( (x+8)/3 ) \n" ); document.write( "graph of equation 1 is: \n" ); document.write( " \n" ); document.write( "graph of equation 2 is: \n" ); document.write( " \n" ); document.write( "graph of equation 3 is: \n" ); document.write( " \n" ); document.write( "graph of equation 4 is: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |