document.write( "Question 184247: 114. Surface area of a cube. The formula A =6V^2/3 gives
\n" ); document.write( "the surface area of a cube in terms of its volume V. What is the volume of a cube with surface area 12 square feet? \r
\n" ); document.write( "\n" ); document.write( "94. Find all real or imaginary solutions to each equation.
\n" ); document.write( "49x^2+9=42x \r
\n" ); document.write( "\n" ); document.write( "98. x-1/x+2= 2x-3/x+4 \r
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\n" ); document.write( "\n" ); document.write( "110. Winston works faster. Winston can mow his dad’s lawn in 1 hour less than it takes his brother Willie. If they take 2 hours to mow it when working together, then how long would it take Winston working alone? \r
\n" ); document.write( "\n" ); document.write( "114. Maximizing profit. The total profit (in dollars) for sales of x rowing machines is given by P(x)=-0+2x^2+300x-200 . What is the profit if 500 are sold? For what value of x will the profit be at a maximum? \r
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Algebra.Com's Answer #138385 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
114. Surface area of a cube. The formula A =6V^2/3 gives the surface area of
\n" ); document.write( " a cube in terms of its volume V.
\n" ); document.write( "What is the volume of a cube with surface area 12 square feet?
\n" ); document.write( "write it:
\n" ); document.write( "\"6V%5E%282%2F3%29\" = 12
\n" ); document.write( "divide both sides by
\n" ); document.write( "\"V%5E%282%2F3%29\" = \"12%2F6\"
\n" ); document.write( "\"V%5E%282%2F3%29\" = 2
\n" ); document.write( "Cube both sides and you have
\n" ); document.write( "V^2 = 8
\n" ); document.write( "V = \"sqrt%288%29\"
\n" ); document.write( "v = 2.828 cu/ft
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\n" ); document.write( "94. Find all real or imaginary solutions to each equation.
\n" ); document.write( "49x^2 + 9 = 42x
\n" ); document.write( "49x^2 - 42x + 9 = 0
\n" ); document.write( "(7x-3)(7x-3) = 0
\n" ); document.write( "7x = 3
\n" ); document.write( "x = \"3%2F7\"
\n" ); document.write( ":
\n" ); document.write( "98. \"%28%28x-1%29%29%2F%28%28x%2B2%29%29\" = \"%28%282x-3%29%29%2F%28%28x%2B4%29%29\"
\n" ); document.write( "Cross multiply
\n" ); document.write( "(x-1)(x+4) = (x+2)(2x-3)
\n" ); document.write( "FOIL
\n" ); document.write( "x^2 + 3x - 4 = 2x^2 + x - 6
\n" ); document.write( "combine on the right
\n" ); document.write( "0 = 2x^2 - x^2 + x - 3x - 6 + 4
\n" ); document.write( " x^2 - 2x - 2 = 0
\n" ); document.write( "Solve this using the quadratic formula: a=1; b=-2; c=-2
\n" ); document.write( "You should get: x = 2.732 and x = -.732
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\n" ); document.write( "110. Winston works faster. Winston can mow his dad’s lawn in 1 hour less
\n" ); document.write( " than it takes his brother Willie. If they take 2 hours to mow it when
\n" ); document.write( " working together, then how long would it take Winston working alone?
\n" ); document.write( ":
\n" ); document.write( "let x = W's mowing time working alone
\n" ); document.write( "then
\n" ); document.write( "(x+1) = brother's time working alone
\n" ); document.write( ":
\n" ); document.write( "Let the completed job = 1
\n" ); document.write( ":
\n" ); document.write( "\"2%2Fx\" + \"2%2F%28%28x%2B1%29%29\" = 1
\n" ); document.write( "Multiply eq by x(x+1), results
\n" ); document.write( "2(x+1) + 2x = x(x+1)
\n" ); document.write( "2x + 2 + 2x = x^2 + x
\n" ); document.write( "4x + 2 = x^2 + x
\n" ); document.write( "0 = x^2 + x - 4x - 2
\n" ); document.write( "x^2 - 3x - 2 = 0; a quadratic equation
\n" ); document.write( "Use the quadratic formula to solve this a=1; b=-3; c=-2
\n" ); document.write( "Positive solution: x=3.56 hrs W working alone
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\n" ); document.write( "114. Maximizing profit. The total profit (in dollars) for sales of x rowing machines is given by P(x)=-0+2x^2+300x-200 . What is the profit if 500 are sold?
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\n" ); document.write( "Assume you mean
\n" ); document.write( " P(x)=-.2x^2+300x-200
\n" ); document.write( "substitute 500 for x
\n" ); document.write( " P(x)=-.2(500^2) + 300(500) - 200
\n" ); document.write( " P(x)=-.2(250000) + 150000 - 200
\n" ); document.write( " P(x)=-50000 + 150000 - 200
\n" ); document.write( " P(x)= $99,800 profit
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\n" ); document.write( "For what value of x will the profit be at a maximum?
\n" ); document.write( "Use the axis of symmetry formula: x = -b/(2a); in this eq: a=-.2; b=300
\n" ); document.write( "x = \"-300%2F%282%2A-.2%29\"
\n" ); document.write( "x = \"-300%2F%28-.4%29\"
\n" ); document.write( "x = 750 unit for max profit
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